This app was mentioned in 2 comments, with an average of 1.00 upvote
I just bought my first ever ukulele so I'm not an expert o anything but I got this app on the Android app store and I think it works fine. Maybe some experts can confirm? https://play.google.com/store/apps/details?id=hai.lior.ukaleletunerfree&hl=en_GB
https://play.google.com/store/apps/details?id=hai.lior.ukaleletunerfree this app will tell you if the string is too high or low and you can adjust from there.