In the app settings you can change the distant limit up to unlimited, and the height too up to 500 metres.
You can probably ignore nag screens about updates indefinitely - provided you don't update the app which might be inevitable if you have to download a new version for a different device.
Eventually the app and firmware might become so different that things wouldn't play well at all.

In general it's probably best to keep both up to date. A lot of the updates ares gimmicky things like live stream to facebook - but they do make subtle changes for example improved battery management or overall stability without giving every detail.