When choosing a mobile phone antenna, you should consider the following factors:
Antenna type:
There are many different kinds of antennas such as directional and omni directional antennas. Directional antennas are best for long-range communication while omni directional antennas are best for short-range communication.
Signal strength:
Antennas are rated in dBi; the higher the rating the higher the signal strength the antenna will achieve.
Connection type:
An antenna needs to be connected to the device to receive the increased signal and it can be connected to devices in different ways depending on the device used.