I have several systems, some new and some used, with dozens of new batteries in the original. box still wrapped in plastic I no longer use the 3DR at our television station and don't have a use for them. I am new to this forum, just looking to see what people are doing with these. I have learned that the app no longer works on my IPAD, so, kind of lost as to what I should do.
Sadly batteries aren't worth that much due to age, but you can use sidepilot or solex as a replacement app. The 3DR hardware is still very good, and the community has kept the firmware up to date with open solo. With a little work you can get them flying better than new.
Thanks for the info. I have 7 Solo drones, and tons of batteries so it would be fun the get them back in the air just for fun. I hadn't explored what others were doing to keep these units flying. Thanks again.