There has been a few discssion topics on using the URI capablity to add an event to the calender on the app. And I have indeed played with it in the past and not been able to get this to work correctly. (Date and time would just not pass). I have not given it much thought as I had been working on other projects, but found that I now have a need to get this working. I have explored the interface and SailForm is indeed broke here (from Android 10 onwards - there appears to be a change in Android which was not resolved in a version of Sailform (and is now not likely to be)
So what are our options - I did see a post where a URL call could be made to CalShare as a proxy web site which then calls Google calender. But it is possible to call Google Web Calender direct using a URL. The solution is actually quite easy (when you know how) - but again dont use the URI intent - this fails with google with a mall formed message - event though I know its 100%.
The solution is to define a text field with a format of WEB - and then press the web icon at to call the URL - and it works a dream.
the structure of that field is shown in screen shots below. - the year needs to be 4 digits and month and day 2 diigits (leading zero),
set up some hidden work fields to format date and time etc (example shown below)
the calender users is a comma seperated list of emails if you want to add other user to the invite - Omit the &add= if its just the default account you want to use.
end time is start + duration (in my example the duration is static 150 mins - but could be replaced with a whole number field.
Enjoy