Without "while" should be accepted.

why can't I write "i play on my phone"? I know its not the literal translation but thats how a decent chuck of people in english would say it

What's wrong with 'While awaiting my colleague . . .'

The word "awaiting" is also correct.

I am playing with my phone was rejected. Playing on my my phone would sound more natural, but I didnt like to try it, then marked wrong anyway!

Play on my phone should be accepted. It is the natural translation

Why can't i write "I play with my phone while waiting for my colleague." ?

It's pretty hopeless when try to catch up after the massive update that Duo failed to warn us about, to be forced to do a listening exercises when the sound has stopped half way through a lesson or test once again. Another heart lost when I skip the exercise! This problem has been raised over and over again and still Duo does nothing about it. I would have thought that sound is fairly fundamental to language learning.

I used the wrong word, unfortunately, with Duos new technique, I cannot see which word... This bugs noone else???

This should be "I will play with my telephone."