Just to put in in perspective - my garmin aviation subscription is $480/yr - garmin takes public data, creates a proprietary format,
and a proprietary download system to load the data cards monthly - the data is married to the unit, so it can't be shared.
To use my garmin unit for primary navigation, I must have this data.
It does not include a weather overlay - that is extra (there is some weather available with the right hardware)
garmin head units start around $8,000. (mine is a legacy model from 20 years ago - and it is hitting end-of-life)
An ipad can not be used for primary instrument navigation, but it can be used for situational awareness. It has weather, color moving map,
can be easily updated, and uses the same public data. $100/yr including app updates. It does replace all paper charts (legally) - and
they would easily cost more than the subscription.
Garmin has to do a better job - from an aviation perspective, they are rolling in the dough.