"on these platforms" is correct and usable in written English.
You can use it when referring to multiple digital platforms, services, or websites. For example, "Our products are available on these platforms: Amazon, eBay, and Etsy."
You can track rideshare drivers using technology and complain about the bad ones on these platforms.
But investors on these platforms are already wary of risk.
But our record keeping on these platforms is a public act, performed for others.
Some $600 billion worth of derivatives trade privately on these platforms - through the phone or online.
Traditional media can help verify and amplify stories breaking on these platforms so they reach those offline.
If Rackspace's strategic shift to sell services on these platforms succeeds, Apollo will have a nice payday.
Candidates should be expected to campaign on these platforms and then to carry them out, with dissidents punished or expelled.
According to our speakers, brands haven't yet cracked the Vine and Snapchat market, but we may see more branded content on these platforms in the near future.
Since they use different search engines and social-media platforms from everywhere else, success largely depends on being blogged about on these platforms.
We'll continue to use the expertise we've built up in-house on these platforms, and to take advantage of the quality of those platforms' SDKs, and the quality of the experiences they can provide.
People don't confess sadness and loneliness on these platforms, as they do to real friends, and that makes all of us unhappier as we assume that other people's lives are more successful than our own.
