Dmytro, if you're still following this thread, let me just say "thank you" as this is a nice app. My only suggestions, if we're writing wish-lists, would be similar to those voiced by some on the Large Format forum etc. (1) The ability to set the "Sound every..." time to something greater than 59 seconds would be good. And (2) Some of the sounds are too short or too quiet. You can't satisfy all the users with the inbuilt sounds, because someone will think it's too quiet, someone else thinks too loud; someone thinks too short, someone thinks too long, etc. Would it be possible to let the user choose from among the alert sounds on the phone, just as we can for texts, ring-tones, email alerts, etc.? It would probably suffice to allow such sound configuration at the Intervallo app top level, not for each timer.
As I said, it's only a wish list. I'm not at all a developer so I've no idea whether these things would be easy or difficult (or impossible). Keep up the great work!
And now, your app and I are going to process some Delta 400 Pro...
--Dave
