Can I install an old version of an app?

[bollweevil]

I am heavily reliant on the app PlainText, version 1.7.7. This version was current when iOS 6 was current, and it has been deprecated and replaced by newer versions. The newer versions lack certain crucial features.

I know I need to find a different app that fills this niche. As a stopgap measure, can I possibly install PlainText v1.7.7 on my new iPhone 6 Plus?

I have the .IPA file (the binary), but I need to get it from my MacBook onto the new iPhone, and iTunes will try to stop me.

How do I do this?

Thanks.

 

[dacreativeguy]

I haven't done it in a while but this used to work:

1. Copy the old ipa version you want out of the iTunes/mobileapps folder and onto your desktop on the mac
2. Delete all instances of ipa versions of that app from the iTunes/mobileapps directory
3. Delete the new version you don't want from your iPhone.
4. Open itunes on the mac, go to your apps, and drag the old version ipa from your desktop.
5. Sync your iPhone. The old version app should sync to the phone.