How is sololearn app so small?

Question

Considering the number of features it has, the sololearn app is just too small in size. How did they do it? Please elaborate a bit since I am learning Android Development so a specific answer will be appreciated.

Answer 1

TempleOS, a fully-featured PC operating system I highly suggest you Google is only 16 MB (standard distribution) or 2 MB (minimal distribution).

Making software small really isn't that difficult.

Firefox takes up only 100MB on my phone, and has many more features then Sololearn. Gmail also takes the same amount, and that is including my emails. Google+ takes the same amount as Sololearn.