You can test the changes on this Pull Request by downloading it from AppCenter here with build number: 22268. IPA is available here. If you need access to this, you can ask a maintainer to add you.

Tested 4faa77d:

Legend:
🤷‍♂️ : not exposed to the apps yet
⏳ : in progress
❌ : failed
✅ : passes
⚠️ : passes but there are notes
🚫 : blocked

⏳ Smoke test
🚫 gb_mobile_1686 Adding retry feature to mobile apiFetch handler. 🚫: Testing instructions assume the WP Media library will allow selecting an image while offline but, it doesn't in my test
✅ gb_mobile_1847 Remove DEV flag from Media Editor button
✅ gb_mobile_1841 Show the media edit icon only if the block is selected
✅ gb_mobile_1835 Make inserter to show options on long-press to add before/after
✅ gb_mobile_1826 Update ref to react-native-slider fork to support autolinking
✅ gb_mobile_1827 Fixes the Image's media button not displaying the Picker
✅ gb_mobile_1872 Add media edit icon to image block
⏳ gb_mobile_1450 Update React Native to 0.61.5
✅ gb_mobile_1799 Adjust to Gutenberg master to fix issues with icons, the primitives package and a new dependency for data
✅ gb-mobile-1856 Fix gallery size labels (tested on 4582b9b)

🤷‍♂️ gb_mobile_1817 External media links from another app will not work if the block editor is enabled. Fixes an Android-only issue
🤷‍♂️ gb_mobile_1830 (DEV only) Fix gallery upload sync
🤷‍♂️ gb_mobile_1825 (DEV only) Fix: fix appender style
🤷‍♂️ gb_mobile_1776 (DEV only) Allow configuration of selection/caret color on Aztec view
🤷‍♂️ gb_mobile_1785 (DEV only) Style improvements for template previews
🤷‍♂️ gb_mobile_1762 (DEV only) Use patch-package to fix max-depth issue in react-native (temporary)
🤷‍♂️ gb_mobile_1821 (DEV only) Fix: AppenderButton and Separator in InnerBlock

Testing issues found on WPAndroid wordpress-mobile/WordPress-Android#11224 (comment):

1. Typing "Enter" to create a new paragraph block causes the blocks list to jump to the top and scroll down to the new block.

This issue is also present on WPiOS

2. Merging blocks by hitting "backspace" doesn't work if you first edit one or more chars from the start of the block. (Not on WPiOS)
3. Quote block "jumping/quirk" trying to add a newline. This seems to already exist in the production app as well.

I didn't find any jumpiness/quirkiness, but there's a small flashiness on the last line. I believe this is an old thing that doesn't seem to be problematic.

4. Keyboard doesn't hide when hitting the "close keyboard" button on the toolbar while being in the shortcode block and the Image caption (same on Code block but that block is behind "DEV" flag). (Not on WPiOS, also tested on Pre-formatted, and the keyboard shows [the field is focused] when the blocks are inserted).

1. Jumpines on new para block:

It's an old known bug described here: facebook/react-native#24011