Search on Telegram is more powerful than in other messaging apps because it allows users to find public channels and bots. Unfortunately, this feature has been abused by people who violated our Terms of Service to sell illegal goods.
To further deter criminals from abusing Telegram Search, we have updated our Terms of Service and Privacy Policy, ensuring they are consistent across the world. We’ve made it clear that the IP addresses and phone numbers of those who violate our rules can be disclosed to relevant authorities in response to valid legal requests.
OK, but it is Foss and encrypted client-side