Line of communicators of the company Palm. Initially worked under the control of the operating system Palm OS (Garnet OS). Later, due to the obvious obsolescence of this OS, they switched to a more promising Windows Mobile. Communicators Treo, being quite popular (especially in the United States) allowed Palm survive difficult times and stay afloat until the appearance of new fundamentally new devices - Pre и pixie.
First Treo appeared in 2002 - the Treo 90 model. This device was still devoid of a telephone module and was an ordinary PDA. But it has already manifested a characteristic for all Treo feature - a hardware QWERTY keyboard, in the presence of a touch screen (although not all devices were equipped with the latter - some budget communicators under Windows Mobile were deprived). Designed by Treo 90 was the company Handspring, which Palm absorbed later - in 2003.
In the same 2002, Treo 180 appears. This model was already equipped with a GSM module. True, in order to reduce the cost, its screen was monochrome (for Treo 90 - color). A more expensive model, the Treo 270 with a color screen, also appears promptly.
A total of 20 models were produced. Treo 700w was the first communicator of the line to work under Windows Mobile (2006). Since then, it has become customary - the presence of a letter in the name w or "v" meant the presence Windows, letters "R" (or the absence of any letters at all, only numbers) - Palm OS. Devices were produced for both GSM and CDMA networks.
The latest model appeared in 2008 - Palm Treo Pro. In early 2009, the company switched completely to devices running the latest Web OS.