Does a contact on an android phone contacts list that shows a Telegram app symbol by it and says "Connected via Telegram" mean it is someone who is chatting on telegram or just someone who also has telegram? None of the other contacts show this
The symbols that appear under 'connected via' are there to show you, where the contact is saved.
So if a number is saved on your Google account, it will show a Google symbol.
Being that apps like WhatsApp and Telegram, sync your contact list and use that for their app, therefore it will show 'connected via' telegram, because you are using that contact in telegram.
In short, when it says 'connected via' it just means that the app in question is using this number. And not that you have ever contacted the person.