Download the Zip files containing the binaries from the Releases section of the git (https://github.com/shivasiddharth/Stremio-RaspberryPi). 

Place the downloaded zip in the /home/${USER}/ directory and unzip the file.

Buster Users:

sudo sh -c "echo 'deb http://ftp.us.debian.org/debian/ buster main contrib non-free' >> /etc/apt/sources.list"    
sudo sh -c "echo 'deb http://deb.debian.org/debian buster main contrib non-free' >> /etc/apt/sources.list"     
sudo apt-get update

Bullseye Users:

sudo sh -c "echo 'deb http://ftp.us.debian.org/debian/ bullseye main contrib non-free' >> /etc/apt/sources.list"    
sudo sh -c "echo 'deb http://deb.debian.org/debian bullseye main contrib non-free' >> /etc/apt/sources.list"      
sudo apt-get update

Replace x.x.xxx with the version numbers on the file.

64-Bit Users:

cd /home/${USER}/Stremio-x.x.xxx-arm64-64-bit/   

32-Bit Users:

cd /home/${USER}/Stremio-x.x.xxx-armhf-32-bit/  

Replace x.x.xxx with the version numbers on the file

64-Bit Users:

sudo apt-get install ./libfdk-aac1_0.1.6-1_arm64.deb ./stremio_x.x.xxx-1_arm64.deb -f   

32-Bit Users:

sudo apt-get install ./libfdk-aac1_0.1.6-1_armhf.deb ./stremio_x.x.xxx-1_armhf.deb -f   

Grab some snacks and enjoy.