In case you hadn't heard, back in August of last year Twitter changed the rules for their API, limiting developers to 100,000 individual user tokens for outside apps (or 200% of then-totals, if the app already had more than 100,000 users). To say the change was controversial would be an understatement. Falcon Pro, a favorite among Android Twitter users, has hit the limit. New users cannot log into Twitter via Falcon Pro. That includes those who have already paid for the app and are reinstalling for a new device or ROM.
Falcon Pro was, and technically still is, one of the most popular paid Twitter clients on the platform.