Good receivers support HDMI 2.0 and HDCP 2.2, so they’ll work with UltraHD 4K displays and sources as well. Good receivers also make wireless streaming a breeze. They can connect dirrectly to internet radio stations and local DLNA servers. 

You can connect your smartphone to your receiver, you can listen to the audio.

Good receivers also support Dolby Atmos and DTS:X sound systems.

The best receiver: Denon AVR-S710W (multiple features, easiest setup)

The second best receiver: Onkyo TX-NR545  (same features are top model, but less easy to set up)

The best affordable receiver: Yamaha RX-V379 ( five-channel home theater, no integrated streaming)