That one is what I use and is probably the best known but there are others. There are apps for just about anything you care to think of. My GP insists on you using one or ringing 111 if you want an urgent appointment and have signed up to another where you get GP video appointments supposedly quickly. I did look at the first but it was so many questions that I used 111 instead when my wife was ill. I haven't tried the other but I imagine it will be clogged up with hypochondriacs by now.
Unlike Apple most Android apps are free but carry adverts. If you don't mind answering the odd short survey you can download Google Opinion Rewards which pays 6p upwards for each survey as app store credit. Multi question ones pay more and I've had some pay 30p or more. I've got £11. 51 credit at the moment with £102.66 lifetime (a couple of years) earnings.