You can get Fido Tablet Data Only Plan at $15 for 4GB per month if you are one of the Fido postpaid wireless customers (with a Fido Talk, Text and Data Plan) now. You can get it from Fido Store or by calling Fido support anywhere in Canada. You don't need to buy a tablet from Fido. But if you need a tablet, you can consider the Samsung Tab A, which is Free with a 2-year data plan.
Note: A one-time Transaction Fee applies for the processing of your service request. This is a great deal. I have been on this service since August 2016 (only 3GB per month) and I am very satisfied with it.