Yep, just like a remodeling company in the South promising that no black people will enter any of the homes of the customers to do the remodeling work - for comfort, of course. Please tell me you'd have no problem with that to save your credibility.
- - - Updated - - -
And in this case there is an increased safety factor from it.
One could make that case about hiring black people as well or having blacks serving customers, since blacks commit crimes at higher rates than the rest of the population...
I am unaware of any negative consequences that white people experience as a result of hiring black people to do work for them, even inside their homes. Well, there was that unfortunate "Late Unpleasantness" prior to which in certain parts of the U.S., having black people remodel, cook, clean, tend your children, serve as wet nurses, chop your cotton, bale your hay, etc. was How Things Are Done, to great social accolades and economic benefit (for the white people, anyway). Nowadays, it is true that white people must pay black people to do those sorts of jobs now but it's still quite socially acceptable.
It's also legal to use whatever criteria you wish to use when you select contractors and subcontractors to work on your home. I am pretty certain that some people do use race as a criteria but only fools actually make it obvious. Wise people rely heavily upon recommendations of others who have had similar work performed and the wisest will hire the best contractors and workers they can afford, based upon quality of work, reliability and price, insurance, bonds, etc. regardless of race. But surely, word of mouth already helps those who wish to hire only from or avoid certain elements to fulfill that wish, without the need for an app. You might ask your neighbor or your cousin or your brother in law who remodeled the kitchen and could you get their names but you are not going to ask your cousin for the name of the cabby who got the family to the airport in record time for that trip to Las Vegas.
The app allows people who feel the need or who, through religious or cultural customs and laws, need to avoid being alone with members of the opposite gender. This is not because these religions view males as being inferior to women, but rather that women are inferior and so weak that they cannot be alone, unchaperoned, with a male who is not a relative, for fear of being corrupted or compromised. Such customs are often enforced through some pretty harsh measures. Sure, it's illegal in the U.S. to carry out an honor killing of the daughter who dared to get into a taxi driven by a strange man and probably those who did such a thing would be tried and found guilty and sent to prison. Doesn't help the dead daughter very much, though. Of course, few consequences in the U.S. would be so dire but they exist and they can be really damaging. What does help is having a way to have a safe ride from a service which will keep her in the good graces of her family and her culture.