A siddur built to be used in place of a printed prayer book, and the detail that makes that possible is that it knows where and when you are.
Zmanim — the halachic times that govern when prayers may be said — are calculated for your location, and the app selects the correct service and inserts the right additions for the date without being told. Weekday, Shabbat, Rosh Chodesh, festivals and fast days each change the text, and getting those insertions right is precisely what is hard about using a siddur unaided.
Nusach options cover Ashkenaz, Sefard, Edot Hamizrach and Ari, so the text matches the community you daven with.
Hebrew is presented with translation and transliteration available, which makes it workable for someone still learning to read the Hebrew at prayer speed.
Further tools include a Jewish calendar, candle-lighting times and a minyan finder.
This is a paid app, bought once, on Android and iOS.
RustyBrick has published Jewish mobile applications since 2008, including siddurim, machzorim and zmanim tools.
