Before I added an external Auber, I used a ThermoPro TP25. It has 4 probes and uses an app on your phone. The range is ok, not great, but I can set temp alarms for each probe. There are probably better choices out there these days.
I still use my TP25 for indirect grilling such as steaks where I need an alarm at say, 133* so I can then do a reverse sear at the end of the cook.