Prayer Book is an iOS app available on the App Store that contains prayers from the Writings of the Bahá'í Faith. While the code is GPL, the Bahá'í sacred writings are copyright Bahá'í International Community, source: https://reference.bahai.org.
To work on the code, download it, run
pod install then open up
baha.xcworkspace in Xcode.
License (Source Code)
Copyright 2008-2020. Arash Payan (https://arashpayan.com)
This library is distributed under the terms of the GNU GPL.
Prayer Book is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
Prayer Book is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with Prayer Book. If not, see https://www.gnu.org/licenses/.