Short answer – No. While an internet connection does give you some really useful features (like remote file upload and support) you can work completely offline while receiving RTK corrections over UHF.  All files can be uploaded via USB directly onto the tablet.  A cool feature with our wireless tablet is that you can take it somewhere with Wi-Fi over lunch and the screen will automatically download files as soon as it has an internet connection. Several of our mining customers working on remote sites use this feature to avoid the hassle of surveyors going to each machine Important point to remember – to get NTRIP corrections, you will need a internet connection. All it takes is a sim card with a data plan.