I'm desperate here.
Earlier, I accessed my modem to check out the IPs in my network. The network was configured with DHCP (with a considerable time to expire), and I didn't recognize 3 or 4 IPs: most of them were smartphones.
So, I disabled DHCP and configure to allow just the devices that I known using MAC address. Feeling more secure, I saw the wifi clients, and I founded this:
(The language in the print is portuguese. Pacote = packet (or package, i don't know) Taxa = rate Economia de energia = energy saving Tempo expirado = I don't know how to translate this because I don't know what it is.)
I will explain: the indicated points are my android smartphone, and others are another devices that I recognized. On first row, my smartphone it's not used. On second row, I have send some messages. On third row, I have just NAVIGATE on Play Store, without download anything. On fourth row, I received just a few messages and I was not using the smartphone. Meanwhile, my parents were using their phones, and you can see the discrepancy of how many traffic their phones received and sent and how many traffic my phone received and sent.
I don't know if this traffic have been always like this, but I noticed it just now. There is no root in my android, I download apps only in Play Store and I don't see any suspicious content when I'm using my phone. The only odd thing that I noticed in my phone is that often I have to click more than one time to the click be registered.
And a VERY important detail: all of this traffic on screenshot have occurred AFTER a factory reset on my android (actually this is the reason why I did the factory reset).
I used Packet Capture and I noticed that some captures are listed, but without data in log. This make sense with the fact that my android is sending a lot of packets (like the print in this post) even when I use simple functions of the phone, like receive (receive, not sending) messages. Well, what it can be? Remembering that I have reset this phone. I should use another program to scan it? I didn't root my android and I don't want to do this.
The question is still unsolved, the smartphone keeps receiving and sending a lot of packets. Any recommendations?