The old problem: “~” is not an allowed character in URLs. The lever that makes it (not) working is not HTTP/HTTPS but whether the URL contains a tilde or not.
curl -v -X PROPFIND --user user:pw https://owncloud.arvixe.com/~user/remote.php/caldavreturns 200 OK
curl -v -X PROPFIND --user user:pw https://owncloud.arvixe.com/%7euser/remote.php/caldavreturns 403 Forbidden
So, to fix the bug, please report to Arvixe that their server should understand properly encoded URLs (even it they say that tilde is allowed in URLs, servers should always understand the escaped form; this is the reason why DAVdroid always sends the encoded URLs when not sure). Can you please do that? You can mention this issue for reference.
For a workaround, you may use an own domain with an own SSL certificate so that you don’t have to use URLs with ~.