developing-mobile-apps

A reference for building mobile apps on iPhone, Android, or both. It covers native tools such as SwiftUI and Jetpack Compose, plus cross-platform tools such as React Native and Flutter.

In plain words
What is it for?
Use it to build native iOS or Android apps, create cross-platform apps, implement mobile user interfaces, connect to native device features, and test view models or app state.
Why use it?
It helps choose an approach based on the app’s platform needs and guides common concerns such as state, threading, storage of sensitive data, testing, list performance, startup time, and rendering speed.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/telagod/code-abyss/developing-mobile-apps
Any agent
npx skills add telagod/code-abyss --skill developing-mobile-apps
Clone the repo
git clone --depth 1 https://github.com/telagod/code-abyss

Made for: Claude Code, Codex.

Per session 47 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 382 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00047 $0.00382
Opus 5 $0.00023 $0.00191
Sonnet 5 $0.00009 $0.00076
Haiku 4.5 $0.00005 $0.00038

Measured 2d ago against content hash ceeda8e6eb5e, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

developing-mobile-apps scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/developing-mobile-apps/SKILL.md · 33 lines

What it actually says

移动开发域 · Mobile

判断先于执行:决定「是否做 / 选什么 / 如何取舍」(栈、方案、架构、权衡)前,先读领域判断内核 skills/_kernel/frontend/SKILL.md——它管 judgment,本秘典管 execution;冲突时以内核判断为准。

原生:iOS(SwiftUI/UIKit) | Android(Compose/Kotlin)
跨平台:React Native(TS) | Flutter(Dart)

iOS 检查项

SwiftUI 优先 | @MainActor 线程安全 | async/await | 依赖注入 | LazyVStack | Keychain 存敏感 | ViewModel 单测+Mock

Android 检查项

Compose 优先 | StateFlow 替代 LiveData | Hilt 注入 | Room 持久化 | key 优化 LazyColumn | remember 防重组 | ViewModel 单测(runTest)

跨平台检查项

列表优化(FlatList/ListView.builder+key) | 状态管理(RTK/Riverpod) | 原生桥接验证 | 冷启动<1.5s | 渲染>55fps

选型

Web 背景→RN | 极致动画/UI 定制→Flutter | 大量原生交互→RN | 极致原生体验→原生

SwiftUI/Compose/RN/Flutter API 详情详见 references/details.md

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 33 lines · 47 tokens per session scan A ceeda8e6eb5e

Subscribe to this mod's changes

developing-mobile-apps is a skill published in the GitHub repository telagod/code-abyss (239 stars, last pushed 1mo ago), licensed MIT. It adds 47 tokens to every session and 382 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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