Bicycle holder for Ulefone Armor

I am a geocacher and I often do bicycle trips. For my old Samsung S3 mini I had a bicycle holder which was a water tight pouch which could be attached to the handle bar.

Now I have an Ulefone Armor, an IP68 smartphone. It is significantly larger than my old phone so that I could not use the old holder. I found a similar pouch at the Swedish store [Biltema](http://www.biltema.se/sv/Bil---MC/MC/Tillbehor/Ovrigt/Mobilhallare-for-smartphone-2000035948/) - but the thick plastic window made opera