Give your thumbs a break from texting and use your computer to text over whats app messenger. 

Before we get going I have to warn you that you can't have 2 of the same whats app accounts open at the same time. This means if you enter your phone number  that the What's App account on your phone is registered to into this method the What's App on your phone will no longer work. So i suggest just getting a dummy simcard you will never use again or if you have a Mobile Broadband Internet connection use that sim card.

What's App Messenger for PC