Something changed since routeros v6.9. Now is not possible connect to mikrotik openvpn from IOS (iPhone) openvpn client ("disconnected <TLS failed>" error).
No problems detected connecting from viscosity (osx) or openvpn (linux terminal).
I have tried different ciphers and other configurations, but no success.
Tested routeros versions:
6.7 working
6.9 no
6.10 no
6.11 no
6.12 no
6.13 no
6.14 no
6.15 no

It is exactly the same problem. With version 6.7 works, but the last build 6.16 does not work.

That may be happening?

same problem, I have 2 Router RB751U-2HnD , are connected with OPENVPN, the client is 6.15, the server 6.7, if I upgrade the server with 6.9 ->6.15 don't work.

It's not only ios. I can't connect anymore from windows GUI with a config that was operational before.
See http://forum.mikrotik.com/viewtopic.php?f=2&t=87297

I found solution and now iOS openvpn client v. (1.0.4 build 140) connects to mikrotik routeros v 6.18.
IOS settings->openvpn->advanced settings->Force AES-CBC ciphersuites (disabled this option).

I found solution and now iOS openvpn client v. (1.0.4 build 140) connects to mikrotik routeros v 6.18.
IOS settings->openvpn->advanced settings->Force AES-CBC ciphersuites (disabled this option).

Thanks, very useful.

I found solution and now iOS openvpn client v. (1.0.4 build 140) connects to mikrotik routeros v 6.18.
IOS settings->openvpn->advanced settings->Force AES-CBC ciphersuites (disabled this option).

Thanks a lot, you saved me!