Tips for Creating Blockchain IOS and Android Applications
CryptoBit News Today1 min read
A blockchain mobile app depends on two early choices: the ledger and libraries it is built on, and the store rules it has to pass at Apple and Google. The tables pair the main development options with the specific crypto policies of each store, since many rejections come from on-device mining, unlicensed exchange features or token rewards.
Building blocks
| Choice | Option | Key facts |
|---|---|---|
| Ledger type | Permissioned: Hyperledger Fabric | Known participants; hosted under the Linux Foundation with open governance |
| Smart contracts | Fabric chaincode | Written in Go, Java or Node.js rather than a special language |
| Consensus | Fabric ordering service | Pluggable crash- or Byzantine-fault-tolerant protocols, no native coin required |
| Privacy | Fabric channels, private data collections | Limit which nodes see given transactions and contracts |
| Public chain access | web3.js | JavaScript libraries linking to Ethereum nodes over HTTP, IPC or WebSocket |
| Native Android | web3j | Reactive, type-safe Java library; Android-compatible, generates contract wrappers, supports wallets and ENS |
App store rules on crypto
| Store | Feature | Rule |
|---|---|---|
| Apple (3.1.5 i) | Wallets | Allowed only from developers enrolled as an organisation |
| Apple (3.1.5 ii, 2.4.2) | Mining | Only off-device, such as cloud mining; no background mining, including in ads |
| Apple (3.1.5 iii) | Exchanges | Trades via an approved exchange, only where the app holds licences |
| Apple (3.1.5 iv) | ICOs, futures | Must come from banks, securities firms, FCMs or other approved institutions |
| Apple (3.1.5 v) | Rewards | No crypto paid for tasks like downloads, referrals or social posts |
| Apple (3.1.1) | Unlocking features | Crypto cannot unlock content; digital goods go through in-app purchase |
| Google Play | Mining | On-device mining banned since July 2018; remote mining management permitted |
| Google Play | Exchanges and wallets | Certified services in regulated jurisdictions; compliance documents may be requested |
| Google Play | Tokenised assets | Declared in the Financial features form; earnings may not be glamorised |
| Google Play | NFTs in games | No paid chance at NFTs of unknown value outside approved gambling apps |
Sources: Apple App Store Review Guidelines, Google Play Console Help, Hyperledger Fabric documentation, web3.js documentation, web3j documentation, The Next Web.
