I see. You can launch one app from another app, but I'm not sure if you can write an app exactly like you're describing. Some Garmin watches, such as Fenix, have built-in hotkeys (like hold Back button) which can do predefined actions, but not "Calibrate Altimeter". They also have a controls menu which gives you quick access to predefined actions (but not exactly the same ones).
Since you have the F5X, your best bet would be to suggest the idea to Garmin.
I already have. We discussed about it with the QA from the Beta DEVs but it's surely not one of Garmin's priorities... which is so wrong I can't speak. Why don't you build the GAIN app from your app and put it in the IQ Store? I think if you find functions that are useful to people, rather than giving them the app to build them themselves you should publish them.
(I can do it, alright but I think it's just and proper that your name appears under it, not mine, at the store)
A gain app would be incredibly simple and anyone can do it. Total ascent and total descent are built in garmin variables, so I don't even need to start with my app. You could do it in one or two lines of code, and if you wanted to use it for yourself, you don't even have to go through the hassle of publishing it in the store -- you can just sideload it. I don't have a problem with you creating that app; it's your idea after all.
But now that there's a couple of apps for applying formulas to Garmin data, you don't even need to go through the trouble of downloading the SDK, learning Monkey C and opening Eclipse. Which is sort of the point.
For now I'd prefer to focus on one app that is flexible and to push the limits of what these watches can do. For example, the code for adding functions and variables to AppBuilder is not hard to write now that I have a parser and a framework, but the real challenge is staying within memory limits.
To me it's way more interesting to say "here's an app that lets you do whatever you want -- see what you can do with it", as opposed to "here's an app that just does one incredibly simple thing". If it was one very useful thing done well (e.g. navigation), that would be a different story. I had almost thought that all the good ideas (available to indie devs) were already taken.
The other problem is that for all but the simplest formulas, you have to test them in the real world and see if they make sense. (e.g. Elevation grade). With my app, if my example formula for grade doesn't make sense, someone else can fix it -- assuming I gave them the necessary tools.
TBH since this is just a fun project for me, I want to focus on the idea that's fun for me.
Dunno if you still need it, but I added distanceToStart to AppBuilder. If you just set that as your formula, you get the distance to start in your device distance units (km or miles).
You can also estimate time to start as follows:
Formula: distanceToStart_raw / avgSpeed_raw Display Format: Time
(Or use speed_raw instead of avgspeed_raw, if you prefer)
(Raw distance is metres, and raw speed is metres per second, which gives you a result in seconds. The Time format displays that as hours:minutes:seconds.)
If I had to focus on ideas that are fun for me, I wouldn't be testing the betas and wouldn't be writing reports. Come on, PLEASE, do the gain and the dist/time to start, take the just credit for it and do it for everyone, not just me. :) (of course I need it, everyone needs it and if you are a little patient, I'm sure I can find at least 5 more IQs that are really really needed, especially in the navigation app).
