This guide is not a cure-all end-all for BlackBerry devices. While it aims to make the devices somewhat usable, there are many constraints and limitations that come with these old cell phones. These issues include outdated security standards, low memory, low storage, and slow data speeds (among other things). These early smart devices use EDGE, CDMA, and GSM networks. These rapidly-aging infrastructures are being pulled out of use, mostly in the US. In Europe, 2G is being phased out and 3G is going to stay active for the forseeable future. Regardless, most of these devices use WiFi and Bluetooth, which keeps them in a usable state.
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