It seems RIM is about ready to phase out the distinctive “Pearl” trackball that debuted with the same-named device in favor of a more efficient solution on future phones. Confirming earlier rumors, an image has surfaced today showing both the upcoming BlackBerry Onyx and entry-level Curve 8520 sporting optical trackpads; an indication that the company might be replicating the move across its entire non-touchscreen lineup.
The transition to optical pads is a logical one for the Canadian phone maker in terms of precision and reliability. Particularly because it would give a more accurate impression of where the cursor is going and eliminates any moving parts, preventing dirt or a broken mechanism from rendering the phone unusable or frustratingly unresponsive at best. Although no official announcement has been made, the Onyx is expected to land as the BlackBerry 9020 on both AT&T and T-Mobile before the end of the year.
https://www.techspot.com/news/35413-rim-phasing-out-trackball-in-favor-of-optical-trackpads.html
