SigCare Free is an Android app that can help you have best possible mobile network signal in your Android smartphone without the addition of any external antenna or changing your physical location. The app works for all kinds of network types G, 2G, 3G or 4G. The app works on a simple principle that if you are located somewhere in the middle of more than one cell towers, then your phone will connect to the one having stronger network signal. So if you are receiving a weak signal in your mobile phone, disconnecting it might force it to connect to the cell tower with a stronger signal.
But because of the same reason, you should not use this app on your Android phone if you are located near only one cell tower which is true mostly for the remote locations or smaller cities. In big cities, usually you are surrounded by a number of cell towers and this app will work better.
After the SigCare Free app is installed, you can launch it and tap on the Run SigCare button. This will make the app disconnect you from the mobile network and wait for a few seconds before attempting to reconnect again. If your phone picks up the signal from a different cell tower, you will get much better and stronger signal this time.
In the SigCare app, you can also see mobile your signal information, for example, the signal strength, the signal type, data type, signal bars, network type and the network technology. The signal power is displayed in terms of ASU which is short for arbitrary strength unit. Depending on your network type, ASU can have different values. For GSM (2G) networks the ASU value can be between 0 and 31, for UMTS (3G) networks ASU value is between -5 and 91, for the LTE (4G) networks the ASU value varies between 0 to 97.
You can get the SigCare Free app for Android from https://play.google.com/store/apps/details?id=hapago.trial_sc&hl=en.