How do I separate received data in App Inventor?

Hey there!
I apologize in advance for my grammar.

I'm just learning App Inventor and Arduino usage.
I'm trying to send multiple decimals to App Inventor from my Arduino using an OTG cable connected to my phone, however,
In my example:
Inside the loop(),
I'm sending a decimal 10 using Serial.println(10); if I press a button on my breadboard.
When the button isn't pressed I'm sending decimal 5 using Serial.println(5);

I've made a text box in App Inventor that receives all sent data from the Arduino and displays it for debugging.
The text box displays my decimals correctly sending a 5 if the button is untouched, and 10 if I press it.
Although my problem is that I fail to read the 5s and 10s in app inventor since the decimals "stack" if I can use that word.

My textbox receives 55555555555555 which obviously isnt a 5 and as soon as I press the button
It starts printing 555510101010.
If I use a Delay(64); after each Serial.println(); it works but slows everything down.
How do I read only the 5s and 10s as they come and go?