اَلسَّلَامُ عَلَيْكُمْ وَرَحْمَةُ ٱللَّهِ وَبَرَكاتُهُ‎
Not all countries have the same islamic date.
For example, today is 16 March. In Saudi/UK etc it is also 16 Ramadaan whilst in my country it is 15 Ramadaan.
I have 2 suggestions

1. Correct Lunar date using location - maybe getting the correct date from Islamic institutes websites automatically
   The abv is abit of a difficult task, given the fact that you would have to do research on every single country, hence my second suggestion,
2. Ask the user which day the moon was sighted, or, for Ramadaan, which day was their first fast.

It is no major issue but rather a small thing im suggesting to help improve

Nevertheless, May Allah reward yourl abundantly for each Salaah every person prays on time becaise of this app and may Allah take yourl from strength to strength

Another suggestion would be to publish 13 & 15 line qurans with recitations/translations for each
verse similar to the Qamar Apps version because their app is having many technical issues recently

جزاك الله خير