To elaborate, I personally didn't get much out of meditation until I starting using it to sit with concepts like impermanence, non-attachment, and oneness from the Zen tradition.
By contrast, apps like Headspace are selling themselves like "feeling anxious? Try our app!" and getting corporate sponsorships for employers to give subscriptions to their employees, like a commodity to pacify a stressed out workforce.
But who knows, maybe it's still a net good in that it might introduce more people to the practice. And maybe some of the apps get deeper into the practice than the ones I used.