# digital wallet Published articles for digital wallet. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## Accept Payments in Africa: A Complete Guide for SaaS Companies DevFeed: [Accept Payments in Africa: A Complete Guide for SaaS Companies]() Original publisher: [Read original article]() Author: Ayush Agarwal Published: 2026-04-05T00:00:00Z Content type: tutorial Language: en Sources: [Dodo Payments Blog]() Topics: [Software as a service](), [Localization (l10n)](), [Transactions]() Tags: [africa](), [bank-transfers](), [card](), [compliance](), [digital-wallet](), [global-expansion](), [guide](), [merchant-of-record](), [mobile](), [payments](), [saas](), [transactions]() ### AI overview This guide explains how SaaS and digital product businesses can accept payments across Africa. It emphasizes mobile money, local bank rails, transfers, USSD, and localized payment methods over card-only checkout, and discusses currencies, compliance, and Merchant of Record services. ### Source excerpt How to accept payments across Africa with the right payment methods, currencies, and compliance setup for SaaS and digital product businesses. ## How to Add Payments to an Expo / React Native App DevFeed: [How to Add Payments to an Expo / React Native App]() Original publisher: [Read original article]() Author: Aarthi Poonia Published: 2026-03-24T00:00:00Z Content type: tutorial Language: en Sources: [Dodo Payments Blog]() Topics: [Expo](), [React Native](), [Software as a service](), [API keys](), [API](), [Mobile]() Tags: [android](), [api-keys](), [digital-wallet](), [how-to](), [ios](), [merchant-of-record](), [mobile](), [payments](), [react-native]() ### AI overview This tutorial explains how to add Dodo Payments checkout links to an Expo or React Native mobile app. It covers using an external web checkout for SaaS and digital services, configuring the backend, protecting secret API keys, and handling deep links after payment. ### Source excerpt Learn how to add payments to your Expo or React Native app using Dodo Payments and WebBrowser.openBrowserAsync() to avoid the 30% app store fee for SaaS products. ## Estimating Incremental Lift in Customer Value (Delta CV) using Synthetic Control DevFeed: [Estimating Incremental Lift in Customer Value (Delta CV) using Synthetic Control]() Original publisher: [Read original article]() Author: Mahshid Moha Published: 2025-02-14T20:41:49Z Content type: article Language: en Sources: [PayPal Technology]() Topics: [Data Science](), [Transactions](), [digital wallet]() Tags: [adoption](), [causal-inference](), [customer-value](), [customers](), [data-science](), [digital-wallet](), [margin](), [monetization](), [paypal](), [products](), [revenue](), [synthetic-control](), [transactions]() ### AI overview This article explains PayPal's Delta CV metric, which estimates the incremental profit margin generated during the first year after a customer adopts a product or completes an action. It distinguishes Delta CV from customer lifetime value and describes direct and halo effects on engagement, revenue, and margin. ### Source excerpt How we measure the impact of user actions and product adoptions at PayPal In today's competitive digital landscape, understanding user interactions with your products is essential for driving revenue and building lasting customer relationships. At PayPal, our Data Science teams use causal inference to evaluate the impact of key customer actions, such as adopting a new product or adding a credit card to their wallet, on engagement (measured by Transactions per Account, or TPA), revenue, and margin to help make data-driven strategic decisions. The direct profit from a product adoption or a user action on the app could be $0 if viewed in isolation. However, that does not necessarily mean that these events are not driving engagement and monetization across the PayPal ecosystem; they can change the user engagement with other PayPal products in such a way that the user starts generating more profit. To measure the overall impact of user actions or product adoption, we introduced Delta CV (delta in Customer Value), and we defined it as a customer's incremental profit margin in the first year after adoption of a new product or completing an action. For example, if the average Delta CV for adoption of Crypto is $20, we expect customers who adopt Crypto for the first time to bring an additional $20 in margin on average in the next 12 months after the adoption. We define Delta Revenue (or TPA) in the same manner except we calculate the incremental lift in revenue (or TPA) instead of profit margin. The concept of Delta CV is very different from customer life-time value (CLV) which estimates the total profit generated by a customer over the course of their relationship with PayPal. Delta CV gives us a wholistic view on how new adoptions affect the engagement and value of an existing PayPal user. Adoption of a new product or completing an action can increase the customer's value in a few ways: The product itself may be a profit generating (Direct effect). For example, paying with ## Blockchain Concepts Explained Through Go Modules and Software Build Problems DevFeed: [Blockchain Concepts Explained Through Go Modules and Software Build Problems]() Original publisher: [Read original article]() Published: 2022-12-12T00:00:00Z Content type: tutorial Language: en Sources: [William Kennedy]() Topics: [Blockchain](), [P2P](), [Database](), [Go Language]() Tags: [blockchain](), [build-blockchain-from-scratch](), [cryptographically-auditable](), [database](), [digital-wallet](), [ecdsa](), [engineering](), [ethereum](), [genesis-file](), [go](), [go-blockchain](), [golang-blockchain](), [p2p]() ### AI overview This video introduces blockchain concepts, including its append-only and transparent database model, cryptographic auditability, and peer-to-peer network structure without a central authority. It explains these ideas through reproducible, durable, and secure software builds and the Go module system. ### Source excerpt Introduction In this video, Bill will introduce the concepts of what a blockchain is, the benefits of a blockchain, and the network environment it operates in. Bill describes a blockchain as a single, append-only, transparent, publicly available and cryptographically auditable database. Blockchains operate using a peer to peer (p2p) network with no single node designated as the central authority. To better understand what all that means, Bill begins to work through a familiar problem of creating reproducible, durable, and secure builds that software teams face. It's a real problem the Go team eventually solved with the new module system. As Bill uncovers different problems that present themselves, he introduces different blockchain concepts that can help provide a solution. ## Practical Uses Of Blockchain Technology DevFeed: [Practical Uses Of Blockchain Technology]() Original publisher: [Read original article]() Published: 2022-06-06T00:00:00Z Content type: article Language: en Sources: [William Kennedy]() Topics: [Blockchain](), [blockchain technology](), [Dependency management](), [Database](), [Cryptography](), [Code]() Tags: [blockchain](), [blockchain-signature-verification](), [blockchain-technology](), [build-blockchain-from-scratch](), [cryptographically-auditable](), [cryptography](), [database](), [dependency-management](), [digital-wallet](), [distributed](), [ecdsa](), [ethereum](), [genesis-file](), [go-blockchain](), [golang-blockchain](), [verification]() ### AI overview The article explains practical uses of blockchain technology, focusing on a dependency-management verification system. The proposed system hashes code retrieved from a version-control system and compares it with a database record to detect changes. Cryptographic auditing and append-only records are presented as ways to make the database verifiable. ### Source excerpt Introduction A blockchain is an integrated solution of different computer science problems in the form of a single, append-only, publicly available, transparent, and cryptographically auditable database that runs in a distributed and decentralized environment. I've heard many times that blockchain is a technology looking for a problem to solve. I disagree with that assessment because the tech and computer science behind blockchain has practical uses in everyday engineering problems. One use of this technology that comes to mind is a dependency management verification system. ## Blockchain In Go: Part IV: Fraud Detection DevFeed: [Blockchain In Go: Part IV: Fraud Detection]() Original publisher: [Read original article]() Published: 2022-05-05T00:00:00Z Content type: tutorial Language: en Sources: [William Kennedy]() Topics: [Blockchain](), [audit trail](), [Go Language](), [Database](), [Code]() Tags: [audit-trail](), [blockchain](), [blockchain-signature-verification](), [build-blockchain-from-scratch](), [cryptographic-audit](), [digital-wallet](), [ecdsa](), [ethereum](), [fraud](), [fraud-detection](), [genesis-file](), [go](), [go-blockchain](), [golang-blockchain](), [hash](), [storage](), [verification]() ### AI overview This fourth post in a series explains how the Ardan blockchain detects forgery or changes to blocks and transaction data. It describes the cryptographic audit trail formed by block-header fields, including hashes linking each block to the previous one, so a node can verify its local blockchain copy and detect mismatches. ### Source excerpt Introduction In the first three posts, I explained there were four aspects of a blockchain that this series would explore with a backing implementation provided by the Ardan blockchain project. Digital accounts with electronic signatures and verification Transaction distribution and synchronization between computers Redundant storage and consensus by different computers Detection of any fraud to past transactions The first post focused on how the Ardan blockchain provides support for digital accounts, signatures, and verification. The second post focused on transaction distribution and synchronization between different computers. The third post, focused on how the Ardan blockchain handles consensus between different computers which results in the redundant storage of the blockchain database. In this fourth post, I will focus on how the Ardan blockchain can detect forgery or changes to the underlying blocks and transaction data. ## Blockchain In Go: Part III: Redundant Storage And Consensus DevFeed: [Blockchain In Go: Part III: Redundant Storage And Consensus]() Original publisher: [Read original article]() Published: 2022-04-19T00:00:00Z Content type: tutorial Language: en Sources: [William Kennedy]() Topics: [Blockchain](), [Go Language](), [Databases](), [Transactions]() Tags: [availability](), [blockchain](), [blockchain-consensus-protocol](), [build-blockchain-from-scratch](), [consensus](), [database](), [digital-wallet](), [ethereum](), [go](), [go-blockchain](), [golang](), [golang-blockchain](), [proof-of-work](), [storage](), [transactions](), [verification]() ### AI overview The third article in a series explains how the Ardan blockchain project handles consensus between computers and uses that process for redundant storage of the blockchain database. It introduces proof of work and proof of stake, discusses safety versus liveness, and notes the consensus approaches used by Bitcoin and Ethereum. ### Source excerpt Introduction In the first two posts, I explained there were four aspects of a blockchain that this series would explore with a backing implementation provided by the Ardan blockchain project. Digital accounts with electronic signatures and verification Transaction distribution and synchronization between computers Redundant storage and consensus by different computers Detection of any fraud to past transactions The first post focused on how the Ardan blockchain provides support for digital accounts, signatures, and verification. The second post focused on transaction distribution and synchronization between different computers. In this third post, I will focus on how the Ardan blockchain handles consensus between different computers which results in the redundant storage of the blockchain database. ## Blockchain In Go: Part II: Transaction Distribution and Synchronization DevFeed: [Blockchain In Go: Part II: Transaction Distribution and Synchronization]() Original publisher: [Read original article]() Published: 2022-03-08T00:00:00Z Content type: tutorial Language: en Sources: [William Kennedy]() Topics: [Blockchain](), [Transactions](), [Go Language](), [API](), [REST API](), [Concurrency](), [Cache](), [HTTP](), [JSON]() Tags: [api](), [blockchain](), [build-blockchain-from-scratch](), [cache](), [digital-wallet](), [distribution](), [ethereum](), [go](), [go-blockchain](), [golang-blockchain](), [http](), [implementation](), [json](), [mempool-blockchain](), [network](), [project](), [rest-api](), [series](), [synchronization](), [transactions]() ### AI overview This second article in a blockchain series explains how the Ardan blockchain distributes and synchronizes transactions between nodes. It describes submission through a wallet, storage in an in-memory mempool, signaling through a goroutine, and propagation to other nodes. It also introduces the HTTP-based REST API used for wallet and node communication. ### Source excerpt Introduction In the first post, I explained there were four aspects of a blockchain that this series would explore with a backing implementation provided by the Ardan blockchain project. Digital accounts with electronic signatures and verification Transaction distribution and synchronization between computers Redundant storage and consensus by different computers Detection of any fraud to past transactions The first post focused on how the Ardan blockchain provides support for digital accounts, signatures, and verification. In this second post, I will focus on transaction distribution and synchronization between different computers (blockchain nodes). ## Blockchain In Go: Part I: Digital Accounts, Signatures and Verification DevFeed: [Blockchain In Go: Part I: Digital Accounts, Signatures and Verification]() Original publisher: [Read original article]() Published: 2022-02-12T00:00:00Z Content type: tutorial Language: en Sources: [William Kennedy]() Topics: [Blockchain](), [Go Language](), [Code](), [Ethereum]() Tags: [blockchain](), [blockchain-signature-verification](), [build-blockchain-from-scratch](), [code](), [digital-wallet](), [ecdsa](), [ethereum](), [genesis-file](), [go](), [go-blockchain](), [golang-blockchain](), [implementation](), [introduction](), [verification]() ### AI overview This tutorial series introduces the Ardan blockchain project, a Go reference implementation intended for learning rather than production use. Part I explains how the project supports digital accounts, electronic signatures, and verification, using Ethereum as a reference. ### Source excerpt Introduction This is the first post in a series that will explore the semantics and implementation details of the Ardan blockchain project. The code is a reference implementation of a blockchain and not intended to mirror any specific blockchain in use today. Even though the code has been engineered with production level coding standards, I wouldn't use this project for anything more than learning. I am using the Ethereum project as a reference and have taken inspiration from that code. I'm hoping that understanding the code inside the Ardan blockchain will give you enough knowledge to understand the code that runs Ethereum. ## How to add Masterpass support to your site DevFeed: [How to add Masterpass support to your site]() Original publisher: [Read original article]() Author: Matan-Paul Shetrit Published: 2017-10-30T18:17:30Z Content type: tutorial Language: en Sources: [Square Corner Blog](), [Square Corner Blog RSS Feed]() Topics: [API]() Tags: [api](), [apis](), [digital-wallet](), [ecommerce](), [how-to](), [payment]() ### AI overview A tutorial explains how to add Masterpass digital wallet support for U.S. sellers using Square's E-commerce API. It outlines adding a Location ID, configuring the callback, and adding a CreatePaymentRequest. ### Source excerpt Get Masterpass digital wallet on your eCommerce site ## Introducing Apple Pay on the Web for Square's APIs DevFeed: [Introducing Apple Pay on the Web for Square's APIs]() Original publisher: [Read original article]() Author: Matan-Paul Shetrit Published: 2017-09-27T17:03:41Z Content type: release Language: en Sources: [Square Corner Blog](), [Square Corner Blog RSS Feed]() Topics: [API](), [Web](), [Code](), [Mobile]() Tags: [apis](), [apple](), [apple-watch](), [code](), [conversion](), [developer](), [devices](), [digital-wallet](), [documentation](), [domain](), [e-commerce](), [mac](), [payment](), [payments](), [release](), [speed](), [verification](), [web]() ### AI overview Square announces Apple Pay on the Web support for Square Checkout and its e-commerce API, allowing buyers to authenticate payments with Touch ID or a passcode on supported Apple devices. Sellers using Square Checkout need no code changes; e-commerce API users must register their domain and adjust their integration. ### Source excerpt Add Apple Pay as a digital wallet option using Square