This may be somewhat off-topic for this site, but after the recent incident with the Keynote update breaking the Satechi remote, I had to search for instructions on how to restore an older version of an iOS app. Since this may come in handy, I'll add my own writeup here.
First of all, you need a copy of the old iOS app. If you haven't synced your iOS device since the update, you'll find it in your iTunes folder:
- locate iTunes folder, e.g. /Users/yourname/Music/iTunes on a Mac
- inside that folder, locate the Mobile Applications folder
- inside that folder, find the file for your iOS app, e.g. Keynote 1.7.2.ipa
- make a copy of that file, just in case
If you don't have the file any more, grab it from a backup (you do keep backups, don't you?). Mac users should be able to easily locate the file in a Time Machine backup.
Now that you've secured the old version, you can go ahead and delete the unwanted version from your iOS device as usual (tap and hold until the icons begin to wiggle, then tap on the (X) symbol to delete the app). Note that you will lose all the changes you made to your content in the app since the last sync (unless the app - like Keynote - is using iCloud to sync the content, then you'll be fine).
- in iTunes, select Apps section in the sidebar
- switch to list view (for convenience - the icon view is slow to scroll when you have a lot of apps)
- connect the iOS device to your computer but don't sync
- find the app and drag it on to the entry for your iOS device
- now sync
This should get the app back. Note that if the app changed its data format, you may not be able to access content created with the newer version. For example, I now have a presentation sitting on my iPad that was converted to Keynote 2.0 format that the 1.7.2 version cannot open.
Credits: I mostly followed the instructions from How To Reinstall Older Version App For iPhone [Quicktip]. Thanks for that writeup!
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