Can I tune into TV7 over WLAN?

With Multicast:

No.

TV7 uses multicast technology to transmit the TV live signal. Technological problems resulting in image and sound interference occur during transmission over WLAN.

While some router manufacturers do have approaches or proprietary solutions for this problem, Init7 does not offer any support for it.

With Unicast/HLS:

Yes.

Disable Multicast on your Apple TV under „Settings" -> „Apps" -> „TV7" (can not be disabled in the TV7 App).

Please note: With Unicast there is a delay of a few seconds compared to Multicast.