As this is a packaged APK and not on Google Play yet, you might have to install the app by enabling "Unknown Sources". [link].
This doesn't mean that this app has virus or can harm your device, but just NOT uploaded to Google Play and you should pay attention while installing apps from outside the Store. 

Fork from OpenSource, Ads Free 🙇, clean UI and Loved ❤️ utility app : Score Counter Android App 🇺🇦, Github

GNU General Public License v3.0

Features added on base :

1. Bluetooth Counter controls :

   1. Remote based counter management : Reads Bluetooth Remote Shutter for iOS and Android with Bluetooth Technology, generally useful for Selfies, Group Shots, self Portraits and Long-Exposure Shots | Works with Most Smartphones and Tablets, to control counters.

   2. This app is compatible with 2 Button Remotes, which costs around ~2$ (Affiliate Links) : Buy on Amazon India, Buy on Amazon.com,

   3. Allows users to manage the scores on the screen using 2 buttons from upto 10m.

   4. Small form factor and low cost of these remotes allows this to be used by the players themselves during matches without any 3rd person.

   5. Zero Setup Effort - Plug-and-play. Literally.

   6. Flexible for 2 player sports like :

      1. On-Court Sports like

         1. Tennis – played on a tennis court.

         2. Badminton – played on a badminton court.

         3. Squash – played on a squash court.

         4. Table Tennis (Ping Pong) – played on a table tennis court.

         5. Pickle ball – played on a pickleball court.

         6. Padel Tennis – played on a padel court.

      2. Off-Court Sports like

         1. Chess – played on a chessboard, but not a traditional court.

         2. Fencing – played on a fencing piste

         3. Boxing – played in a boxing ring

         4. Wrestling – played on a wrestling mat.

         5. Arm Wrestling – played on a table

         6. Shooting (Archery) – played on a range or field.

         7. Darts – played at a dartboard in a pub or arena, not a court.

         8. Esports – video games played in arenas or online environments.

      3. And a ton of others place where a score counter and display would work. :-)

2. Support for landscape mode on score counter which auto hide controls for larger display.

Remote Setup :

Make sure the Bluetooth remote has 2 button to control the 2 individual score counter.

Pairing :

This can differ significantly in different remotes manufacturers. Please consult the manual received with the remote

1. Turn on the Bluetooth Remote Shutter

   1. Tweak the side power switch or hold the power button on the remote until the LED indicator starts blinking. This indicates the remote is in pairing mode.

   2. Please refer to specific Bluetooth remotes for pairing.

2. Enable Bluetooth on Your Smartphone or Tablet (Android Only)

   1. Go to Settings > Connected Devices > Bluetooth.

   2. Toggle Bluetooth ON.

3. Search for the Bluetooth Remote Shutter

   1. On your device, under Bluetooth settings, look for a new device, usually named something like "Remote Shutter" or "AB Shutter".

   2. Select the device name to pair.

4. Complete Pairing

   1. Once selected, your phone or tablet will pair with the Bluetooth Remote Shutter. You may hear a beep or see a solid LED light or the light might turn off on the remote indicating successful pairing.

5. Test the Remote Shutter

   1. Open your camera app or any photo app that supports remote shutter control.

   2. Press the shutter button on the Bluetooth remote to take a picture.

6. Once paired, no future pairing is required. Next time just, turn on the Remote, turn on your mobile devices bluetooth, select the remote and start the App.

Remote Controls :

Operations and Button mapping:

1. Open App and navigate to Score counter section.

2. Tap on the + on the top navigation bar to add new counters.

3. Tap again to add more.

4. Each Bluetooth Remote Shutter buttons would control 1 counter each. (Two buttons)

5. Increment : To add 1 point to the first counter: Press Button 1.

6. Increment : To add 1 point to the second counter: Press press Button 2.

7. Decrement : To subtract 1 point from the first counter: Double-click Button 1.

8. Decrement : To subtract 1point from the second counter: Double-click Button 2.

9. To reset all scores counter : Long Press and hold either Button 1 or 2 for few seconds .

10. Only first 2 Counters can be controlled remotely. Other counters follow the usual increments by device's screen.