Tools: Do not run "pod install" by default

packages/app-mobile/tools/podInstall.js

@@ -3,6 +3,16 @@ const execa = require('execa');
 module.exports = async function() {
 	if (process.platform !== 'darwin') return Promise.resolve();
 
+	if (!process.env.RUN_POD_INSTALL) {
+		// We almost never need to run `pod install` either because it has
+		// already been done, or because we are not building the iOS app, yet
+		// it's taking most of the build time (3 min out of the 5 min needed to
+		// build the entire monorepo). If it needs to be ran, XCode will tell us
+		// anyway.
+		console.warn('**Not** running `pod install` - set `RUN_POD_INSTALL` to `1` to do so');
+		return Promise.resolve();
+	}
+
 	try {
 		const promise = execa('pod', ['install'], { cwd: `${__dirname}/../ios` });
 		promise.stdout.pipe(process.stdout);

readme/dev/BUILD.md

@@ -49,12 +49,21 @@ You can also run it under WSL 2. To do so, [follow these instructions](https://w
 
 First you need to setup React Native to build projects with native code. For this, follow the instructions in the [Setting up the development environment](https://reactnative.dev/docs/environment-setup) tutorial, in the "React Native CLI Quickstart" tab.
 
-Then, for **Android**:
+### Android
+
+Run this to build and install the app on the emmulator:
 
 	cd packages/app-mobile/android
 	./gradlew installDebug # or gradlew.bat installDebug on Windows
 
-On **iOS**, open the file `ios/Joplin.xcworkspace` on XCode and run the app from there.
+### iOS
+
+On iOS, you need to run `pod install`, which is not done automatically during build time (since it takes too long). You have two options:
+
+- Build the app using `RUN_POD_INSTALL=1 yarn install`
+- Or manually run `pod install` from `packages/app-mobile/ios`
+
+Once this is done, open the file `ios/Joplin.xcworkspace` on XCode and run the app from there.
 
 Normally the **bundler** should start automatically with the application. If it doesn't, run `yarn start` from `packages/app-mobile`.