batteries There are many high-capacity "extended" batteries available for the HTC Universal. 2600mAh, 3150mAh, 3200mAh, 3800mAh, 4800mAh and even 5200mAh models have been sold by various retailers, which allow the device to run for more than a week in many cases on a single charge (with light to medium use). All extended batteries have one big drawback though, they are all supplied with a new plastic back to hold the battery, which considerably increases the size and weight of the device. The 3800 mAh battery is a Li Ion battery with model number PU16B manufactured by Dynapack International Technology Corporation in Taiwan. It is rated at 3.7 VDC (or 4.2 VDC). It increased the weight of HTC Universal to 350 g. It allows the use of the camera by holes built in the battery plastic container. Its price is about 30 EUR as of October 2008. With this battery, HTC Universal can operate up to 200 hours without GSM/UMTS/Bluetooth/WiFi or about 100–150 hours with UMTS and Bluetooth on. Unofficial extensions With registry editing and/or ROM re-flashing (both of which should only be done by people who are confident and experienced with these processes), substantial extra functionality can be added to this device. A few examples follow (there are many more): Wireless G (802.11g) connectivity. This only allows the device to communicate using the 802.11g protocol instead of 802.11b, it does not give a speed increase beyond 11 Mbit. However, numerous online sources now say this no longer works. Full emulation of an "SD card reader" (USB mass storage device class). Full VGA (640 x 480 resolution) graphics, as opposed to the "QVGA (320 x 240) emulation/compatibility mode" which the Universal runs in by default. The two main downsides to this are that some software cannot handle "true VGA" mode, which usually results in corrupted graphics, and that it can be quite difficult to see (and use a stylus with) such small screen elements as text. Emulation and mapping of additional keys not found on the Universal native keyboard, such as CTRL and ALT. Support for SDHC cards. 8 GB, 16 GB and 32 GB cards have been tested successfully. This is only made possible via a third-party hacked driver. 128 MB of RAM. It is possible to replace 64 MB memory modules with 128 MB one. It can be only used with 128 MB enabled ROMs but it makes more