Internet, mobile, PC and Fiber Optics come at 1, 2, 3, and 4 in the top 25 innovations in the tec world. Which innovation occupies the 5th position?

It depends upon your own priorities. I would say smart phone becoz its a paradigm shift

Cloud application deployment method!

Satellite Communication.

RF Communication

VIDEO CALLING

I agree with SATELLITE as the5th.  But for email, I would rate it around10 since email has been around since1975.

Thank you gents. What about EMAIL

INTERNT COMS FIRST

It is really difficult to point out one as it would differ for each country, but something which is really important and a common denominator for every country and individual would be 

Renewable Green Tech Enery

5th place goes to ANDROID APPS  :)!!!

batteries

AND

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