Check your mobile device.

11:49 Aug 31, 2016 

I will keep on searching this matter and share if I can find something definitive. Thank you for your valuable feedback.

10:23 Aug 31, 2016 

Anyway, I was unable to find a definitive reference on the gramatically "correct" form...

10:20 Aug 31, 2016 

I think we are talking about different things. Your last example pertains to the use of "being sure"; I am talking about "making sure"...

10:06 Aug 31, 2016 

The usage will depend on context for sure. The examples you have given are certainly correct and would be wrong if used the other way. However, when we search "olduğuna eminim" and "olduğundan eminim" using web search engines, the former surpasses the latter by far. At the moment, I tend to think that both are valid and correct depending on the context but I remain open to be convinced by good evidence.

09:48 Aug 31, 2016 

Apparently, but I have never used that form in my life, so it sounded "strange" to me... As Hakkı Devrim put it, "Yarınından (yarınına değil) emin olmak, Ahmet'ten (Ahmet'e değil) emin olmak demez miyiz?"

09:24 Aug 31, 2016 

As far as I can see, both are widely used, Recep bey.

06:52 Aug 31, 2016 

The asker just wants to shorten the translation as "Check your mobile device" and asking if "Mobil aygıtınızı kontrol edin" is correct. The answer: it is correct :) He doesn't ask anything else I guess?

06:08 Aug 31, 2016 

Shouldn't it be "düzgün çalıştığından", Selçuk Bey?

05:51 Aug 31, 2016 

... you may prefer "Mobil cihazınızı kontrol ederek her şeyin düzgün çalıştığına emin olun.", which sounds more fluent in Turkish and you will save 14 characters.

03:43 Aug 31, 2016 

In Apple's localizations they prefer "aygıt"; in Windows platforms it is "cihaz" predominantly, and with Android it is also "cihaz" ("Android cihazınızı" has 82,000 search results, while "Android aygıtınızı" has only 56]