Sure, I was looking at the top apps just now. Apparently OpenAI is explicitly okay with WhateverChat powered by ChatGPT.
This is pretty typical for the App Store / Play Store and isn’t anything particular to OpenAI. If there is a third-party service Foo that app Bar uses, then “Foo Bar” is questionable for trademark reasons and the common practice is to use “Bar for Foo” instead.
Very many did that or implied an association with OpenAI, which is why OpenAI had to release updated branding guidelines (https://openai.com/brand) and started enforcing takedowns against apps/domains using GPT in their name.