Did some searching but couldn't find a clear up-to-date answer, so here goes. Use a Google Voice number instead of your real number when you're still getting to know someone.
Faith-based and community-specific apps tend to have much higher conversion rates to actual real dates. Never share your real last name, address, or workplace before meeting someone in person for the first time.
The discreet affair app market has grown substantially but verification quality varies enormously.