Can I tether my cell phone to Orbi RBR50?

No. RBRs require a ethernet service connection from a modem or ONT. 

---

WorkingMan wrote:

I'm looking for the best way to use my cell phone data for my home network. I just bought this Orbi system a few months ago. I've been very happy with it but my ISP is terrible so I want to use my cell phone.

 

If the RBR50 won't work what is my best option?

---

FURRYe38is correct that the Orbi router (like EVERY WiFi router I have seen) is designed to connect to a network with an ethernet cable.  What many people do when the local ISP service is unacceptable is get an LTE modem that connects to their cell carrier (AT&T, Verizon, T-Mobile, EE, depending on country).  These are often sold as "HotSpots" with WiFi built into the box.  If the original ISP wifi modem coverage was inadequate, which led to purchasing the Orbi, then a HotSpot WiFi coverage may be inadequate as well.  In that case, it is probably less costly to purchase an LTE modem that does not come bundled with router and WiFi capability.

I, personally, would not be able to use my cell phone to provide internet because I have so many devices in the house that need internet connection when I am not at home (and take my cell phone away with me).

I have dedicated cell phone for internet now. Just have to figure out how to use it best.