I made a custom data field for myself, and then I found out I had to upload it to the store to be able to use settings in the Android GC app. So this thread is to support that, any questions/problems/comments, etc., let me know.
Flexirunner
https://apps.garmin.com/en-US/apps/ce1e0b46-7c83-4ddb-9d48-c93edadabe3d
Flexirunner is (yet another) all-in-one data field, for use in a single field layout. It is designed for running, with a native look and feel.
It shows time, distance, number of laps, heart rate, pace, and cadence. It also measures running economy (http://fellrnr.com/wiki/Running_Economy), and records this and energy expenditure (https://www.firstbeat.com/en/science-and-physiology/energy-expenditure/) into the FIT file, for later display on Garmin Connect.
Please see the page in the Connect IQ app store (above) for the list of features and screenshots (to avoid re-posting the same thing here).
I have tested this field with my FR235, but it should perform identically on the FR230, FR630, FR735XT. Since version 5, Flexirunner is now also compatible with FR920XT, Fenix 3 & HR & Chronos, vivoactive & HR!
Since development is primarily focused on me having an FR235, the layout is currently most optimized for the semi-round watches.
Donations
If you use & like this data field and you're feeling generous, donations are gratefully accepted (but not obliged) here (give what you feel!): https://www.paypal.me/imgrant
Source code
The source code for Flexiruner is freely available on Github: https://github.com/imgrant/FlexiRunner
You can also raise issues there.
Acknowledgements
The Flexirunner icon incorporates elements by Freepik (http://www.freepik.com) from www.flaticon.com, which are licensed by Creative Commons BY 3.0 (http://creativecommons.org/licenses/by/3.0/).