Google and Amazon urged to follow Apple's 'anti-gay app ban'
Campaigners have thanked Apple for removing an app from its store that they said stigmatised LGBT people.
The software promoted a US religious group that says homosexual practice is sinful and that its members should help "call up" others to their natural-born "biblical gender".
Apple's store now says the app is not available, but the tech firm has not commented on the matter.
Google and Amazon continue to offer Android versions of the app.
The Christian organisation involved, Living Hope Ministries, has told NBC News that it plans to challenge Apple's action.
The Arlington, Texas-based body is not related to a UK-based church that goes by the same name.
Apple's rules state that apps should not include content that is "defamatory, discriminatory, or mean-spirited" including commentary about sexual orientation.
Living Hope Ministries' app had been on the iOS App Store for several years, but was flagged as objectionable by Truth Wins Out on Thursday.
The Chicago-headquartered non-profit campaigns against homophobia.
It launched an online petition against the app after the group's founder claimed to have been given "the run-around" by Apple's staff when he called them to complain about the app's existence on its platform.
In 2014, Apple's chief executive Tim Cook became the first Fortune 500 company leader to announce he was homosexual, and earlier this year told CNN that being gay was "God's greatest gift to me".
Although it is not known whether he had anything to do with the subsequent removal of the app from Apple's online store, Truth Wins Out personally thanked him and his company for "exemplifying corporate responsibility".
But it added: "Google and Amazon [must] immediately stop selling and promoting this app, which dehumanises LGBT people."
The executive director of Living Hope Ministries, Ricky Chelette, said he had not been told in advance that the app would be removed from Apple's store and denied it was a hate organisation.
The BBC understands Google intends to review the product and will remove it if it believes it contravenes its ban on content that incites hatred against individuals based on their sexual orientation or gender identity.
Amazon is also looking into the matter.