Story UPDATE after a further tweet from the developer:
Good news! Turns out a recent bug on twitter makes it look like we ran out of user tokens - We're not! Workaround inbound! #BackInBusiness
Which is good news, though of course the limit is still lurking in the middle distance. See here for my Twitter client roundup (missing Aeries, but I'll fix that shortly).
Original story below...
From the Peregrine team's tweet:
Looks like we finally (and sadly) hit the 100,000 twitter user limit and have to close up shop. Thanks for a great time!
A great shame, though as a genuinely free client it was bound to get high numbers of downloads. The more polished Aeries and Tweetium clients are both commercial and with non-trivial purchase costs, so they should be available for some time to come. Yet another reason to pay something for an application? i.e. it pays the developer's bills and prevents massive downloading by all and sundry.
In an ideal world, Twitter wouldn't have such a limit, of course, but that's a philosophical debate for another day.
If you already have Peregrine installed then in theory you can carry on using it, even putting it onto a new phone - it's just completely new users who are blocked out - but I'd expect the app to be pulled from the Store shortly to prevent confusion, so act quickly if you want it to be shown in the Store.