The Palm Treo 650 is a Palm OS-based smartphone, the successor to Palm's Treo 600. It began shipping in November 2004, and was discontinued in 2008. Specifications Carriers The following GSM and CDMA2000 mobile phone operators currently or previously offered a custom-branded (OEM) version of the Treo 650: In release order Sprint PCS (USA) Cellular South Cingular Wireless (including AT&T Wireless customers) (USA) Unlocked GSM Rogers Wireless (Canada) Verizon Wireless (USA) Earthlink Wireless (USA) Bell Mobility (Canada) Telus Mobility (Canada) Alltel (USA) Centennial Wireless (USA) As seen on Palm's support page, these carriers are the sole providers of support for the OEM phones. Other carriers Nextel (USA) and other iDEN providers are not compatible with the Treo 650, as this technology has not been integrated into the Treo platform. T-Mobile (USA) and other GSM carriers not listed above are compatible with the unlocked version of the GSM Treo 650. NVFS controversy At the time of its release, a significant number of users experienced problems with Palm's new Non-Volatile File System, or NVFS, based on the FAT filesystem. Compared to the Treo 600, the previous version of the Treo, the Treo 650 used more memory per file as the FAT filesystem rounded file sizes to the next highest 512-byte multiple. Because of the larger file sizes, some users upgrading to the Treo 650 from the Treo 600 were unable to fit the contents of their old device into the same amount of memory on the new device. To remedy the initial complaints, Palm offered a free 128 MB SD flash card to Treo 650 users. Later ROM updates have resolved many of the performance, instability and storage inefficiency issues. Other main concerns surrounding the Treo 650 (during its initial release period) were as follows: Some users experienced random resets at one time or another. Although the cause was unknown, a complete reset via the Reset button on the back of the phone under the battery door could keep the phone stable and running most of the day. Some users also reported problems with the unit's microphone. They claimed that voice clarity on the recipient's end of the connection was poor, akin to talking "inside a cardboard box." (koreth, Slashdot). Users have found that bluetooth-enabled wireless headsets or fixed headsets seemed to be an effective work-around. Another problem people reported is that the handset's earpiece made it difficult to hear in loud