Tips and Tricks

Communication Stability

Ensure your android operating system is not optimizing battery usage of AndroidAPS.
Ensure the AndroidAPS app does not have any background data restrictions - this will otherwise interfere with omnipy.

If you are using xDrip, make sure it does not have access to turn bluetooth on and off. If you cannot do that, disable all settings related to 'bluetooth workarounds' which suggest turning bluetooth off and back on. This may result in losing bluetooth tethering until you manually re-enable it.

Use the latest software & image, always.
Make sure your Raspberry Pi and RileyLink are not farther away from each other. Try to keep them as close as possible. Some raspberry pi's apparently have BLE range issues and the RileyLink does not have the best BLE reception either.
Make sure your Raspberry Pi is powered properly. Use good micro-usb c cables that are rated at 5V 1A (AWG 24 or better) least. Don't use cables longer than 15cm if possible.
Don't configure a WiFi access point on your raspberry pi if you don't use it. This puts less strain on the Broadcom chip which handles all bluetooth and wifi connections.
If you always connect via wifi and don't use bluetooth tethering, disable the tethering service: sudo systemctl disable omnipy-pan.service

Make sure your RileyLink is not on running on low battery, whether the leds are blinking or it seems to be working, is not good enough.
Make sure your RileyLink's 433 MHz antenna is performing. One way to measure that is to look into the packet logs and omnipy.log to check if there is a significant number of repeats during message exchange.
If you suspect that the communication between the Pod and RileyLink is not optimal, have a look at the wire antenna option. I cannot overstate the amazing range of the simple wire antenna.
If you cannot afford to build the custom antenna, don't let the RL sit far away from the Pod. If you're frequently going away from the RL, put it on a high place.