You can define an URL, based on a on attribute, in ArcGIS Online. This is a realy nice feature to create a simple interface to external web-based sources. 
When using this webmap in the collector app this works fine on Android 4.4. When pushing the link, it automaticly was opening a browser (Chrome for example), and showing the right webpage.
But 2 weeks ago this stops working. What is happening now, is that collector tries to open the resulting URL inside the Collector app, in the attribute window.
I'm not sure, but I think this behavior started after the upgrade of the tablets (Samsung galaxy Tab S 10.5") to Android 5.01
If you do a completely fresh install of the tablet and the collector app, it works again as it should be, but after 1 or 2 days that odd behavior is back again (opening the url inside of the attribute window of the collector).
Anybody know this behaivior or better, knows how to repair this?
Kind regards,
Bert