I was the first brother in my congregation to turn up to the KH with a tablet. Actually, it was a Kindle with PDFs of the Watchtower on it and the NWT in .mobi format.
I got a good scolding in the back room and lots of snide remarks my the holier than thou members for being "showy". One elder told me "The bible is your sword, how are you supposed to preach with a tablet?".
Fast forward a year, tablets were ok but absolutely not to be used on the platform.
Another year and everyone is encouraged to buy a tablet.
Now? If you dont have a tablet you cant follow along and are regarded as not keeping up with Jehovah's org.