How to see cellular signal strength on Android and iPhone

Our new smartphone does not perform well at home or in the office, despite having changed the mobile network operator on Android and iOS, without simply relying on the notches above (which can say anything and everything).
At the end of the guide we will also suggest some apps that we can use to be able to thoroughly study the type of signal present and the distance from the operator's antenna, so as to obtain other valuable information on the quality of the network.
READ ALSO: 2G 3G 4G coverage map for mobile and internet (Tim, Tre, Wind, Vodafone)
1) Check signal strength on iPhone
On the iPhone there is a secret menu where you can check the cellular signal level in dBm (i.e. in decibels per milliwatt).
To open this menu we will first have to check the phone to see if it is compatible with the secret menu.
Let's go to the Settings app, click on General and then the Info item; from here we take the path Legal Notes -> Regulations . At this point we check the text written in the first line, to see if we have one of the following compatible models:

• iPhone X: A1901
• iPhone 8: A1905
• iPhone 8 Plus: A1897
• iPhone 7: A1778
• iPhone 7 Plus: A1784

If the model matches, then we can go back and open the Phone app, the one where the numeric keypad is present.
From here we type the following number and press the green button to access the secret menu:
* 3001 # 12345 # *
Inside the secret iPhone menu, we select the LTE item and then Serving Cell Meas .
To check the quality of connection to the cellular network, check the values ​​expressed on the items rsrp0 and rsrp1 .
Remember that this scale of values ​​(in dBm) is negative, so it works in reverse: a number closer to zero is an indication of a good signal, while the higher the number, the worse the signal is.
For convenience we can use the following scale as a reference.

• -90 dBm up = Excellent
• -91 to -105 dBm = Good
• -106 to -120 dBm = Weak
• -121 to -124 dBm = Very weak
• -125 dBm = No signal

2) Check signal strength on Android
On Android it is much easier to control the signal strength, since it is a menu accessible from the settings of any device.
We then open the Settings app, go to Info on the phone, then click on Status -> SIM Status, so as to view the signal strength.
This will show the signal in dBm, exactly as seen on the iPhone; the reference scale is the same.

• -90 dBm up = Excellent
• -91 to -105 dBm = Good
• -106 to -120 dBm = Weak
• -121 to -124 dBm = Very weak
• -125 dBm = No signal

If we have a Dual SIM smartphone, we will have two SIM status in the dedicated menu, so we can control the signal strength with two different operators.
On some Android phones we can access the secret menu by acting from the numeric pocket, as already seen on the iPhone.
In this case the codes can be very different according to the manufacturer, so our advice is to try them all to see which menu opens:

• * # * # 7262626 # * # * - Field test
• * # * # 4636 # * # * - Information menu
• * # 0 * # - Information menu
• * # 12580 * 369 # - Information on software and hardware

Let's try and confirm to see what happens on our Android smartphone, taking care not to touch any dangerous item and not to overdo the changes (we could damage the phone without knowing it!).
3) Best apps to control signal strength
If instead of using secret codes or menus we prefer to use apps, there are many available for Android and iOS that can control the intensity of the cellular signal and show it on the screen with many other additional information.
The best apps in this regard are the following.
IPhone app
The apps that we can use on any iPhone (even the newest or oldest ones not mentioned at the beginning of the guide) are:
- Cell Phone Coverage Map : allows you to obtain and create an LTE signal map, so you can immediately view the signal and compare it with the data collected by other users.
- LTE Cell Info : paid app useful to discover all the necessary information on the state of the cellular network.
- OpenSignal : very useful app to understand the signal quality and compare it with the results obtained by other users in the area, also based on the type of operator used.
Android app
On Android, apps of this type are considerably more numerous, so we made a selection of those that we believe are the best to try:
- LTE Discovery : definitely one of the best apps for obtaining precise and detailed information on LTE network coverage or of any other nature (including 3G and 2G), complete with information on the transmission tower, its direction and power.
- Network Cell Info Lite : very nice app from the graphical point of view, with a hand to indicate the signal strength and other very useful information to understand the distance from the transmission tower.
- Netmonitor : with this app we can monitor the LTE or 3G signal every time we move, so as to have an accurate graph of the signal strength and thus discover the areas of our city where the operator in use takes better.
- OpenSignal : the same app seen on iOS, here it is even more accurate and with much more information related to the cellular network signal, with indication of the tower, integrated speed test, signal map for each Italian operator (to which we can contribute ) and other statistical information useful for viewing the information requested.
More information on all these apps can be found in the dedicated article below.
READ ALSO -> How to check LTE cellular signal intensity on smartphones