iPhone 6 & iOS 9 - ad hoc app will not install I'm having problems installing our developed app (distributed via ad-hoc) to iOS9.

The ipa installs and works fine on iPhone 4 and on iPad 2 (iOS 9.1) but nothing seems to work for iPhone 6 with iOS 9.1.


I've tried to install it with iTunes - install stops at ~60-75% and app icons turns grey, then tapping it just says waiting under the icon and nothing else.
Tried to download ipa file from website via safari - safari says it can't download this kind of file.
Re-build and archived, selected distribute using ad-hoc and installing via iTune. Nothing happens - app icon won't even appear in iPhone and iTunes says installing next to app, sync icon in iPhone disappears after a second. The same ipa works fine on iPhone 4 &amp; iPad 2.


iPhone 6 &amp; iPad 2, iOS version: 9.1 (13B143)

iPhone 4, iOS version: 7.1.2 (11D257)

Nothing shows up in device logs (xCode - Window - devices - device logs). I tried to restart between the installs to ensure nothing was cached. Tried to hard reset (?, on/off button + home button). I'm at the end of my wits, nothing seems to work and I it won't tell me why it doesn't work.
I've been working with this problem the whole day now and I've cleared few things up. First, ad-hoc deployment method is not what I'm actually looking for, in my case correct method is enterprise deployment. I'll get back to it later.

I think my problem was in provisioning profiles, because when I added iPhone 6 to devices list (in apple developer center) and included it in provisioning profile, the app installs just fine. Although, when I disabled iPad from devices list it still worked, weird.

I needed to distribute the app outside of the App Store but I wasn't really sure what deployment method to use. Now I think I finally made some sense in them. 

Ad-hoc deployment


meant to use for testing and in-house apps
distributed outside the app store
devices on which the app is used must be added to devices list in apple developer center and selected in provisioning profile
maximum of 100 devices 


Enterprise deployment


meant for in-house, private apps (eg. intranet)
distributed outside the app store
unlimited devices


Difference between them is that ad-hoc is available for everyone while enterprise is only available to developer or team which is under enterprise account. Enterprise should be registered by the company which will be using the private app (eg. intranet app) and add developer (or agency) under it. This way they don't depend on each other and can keep finances separate. 

I'm sure I've still misunderstood something, so if you find any incorrect information here, please do tell.