Telegram or Whatsapp?

I live in India and here WhatsApp and Telegram are the most popular messaging apps. WhatsApp has become so popular that its pretty much the first app people install when they buy a new device. I know that Signal is a robust open source messaging app but no one uses it here, and I don’t think people will even switch to Signal. I also use Telegram but I don’t really know how secure Telegram is for messaging, I think Telegram is not E2E, so the question I have is which should I use more WhatsApp or Telegram?

Telegram, it has open API. you could do a lot of fun stuff with it’s API opposed to closed WhatsApp API