I was just going to post a similar experience so replying here instead.
I have the same issue with the BTECH DMR 6x2 PRO. Firmware 1.10 and 1.20.
Confirmed, aprsdroid connected to the BTECH I can send out a packet and I get picked up on aprs.fi by a local repeater. I made sure the phone was not connected to the internet and communicating to the radio via AFSK.
Now I'm testing with two HT, one BF connected to aprsdroid and I do see aprs packets from other hams, confirming I'm receiving. I have my BTECH sending out APRS, I see the message on the display, TX lights up and RX on the BF lights up but I'm not seeing packets in aprsdroid.
What I did notice is I left the HT beaconing every 30s for an hour and I came back and I did see a single packet from the BTECH on the aprsdroid. The HT are sitting next to each other. I'm expecting each time I beacon out, a packet shows up in aprsdroid.
I followed YT videos on setting up the anytone and looked at the BTECH manual to confirm aprs settings are good. I'm not sure what the problem is but I think it's some setting as aprsdroid sends out reliably over RF.
I'm also want the BTECH to display aprs packets information on the device just to confirm it's receiving but I have no idea how this is done.