Nextivity Cel-Fi RS2 3G review

Can this 3G extender provide coverage where your mobile network provider can't reach?

Nextivity Cel-Fi RS2 3G
These 3G mobile signal boosters come locked to your network

TechRadar Verdict


  • +

    Fills the gaps left by mobile networks

  • +

    Impressively powerful, working through walls


  • -


  • -

    Units locked to set mobile networks

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Strong 3G coverage has become an essential requirement for any small business, especially when it comes to important client phone calls. However, many rural areas in the UK still lack even the weakest of cellular signals. While the new 4G network - which promises far better coverage - goes through a tumultuous legal process, Nextivity believes its Cel-Fi RS2 3G booster can provide a solution.

The booster consists of two parts: a 'window' unit, which sits in the area of the building with the strongest 3G signal, and a 'coverage' unit, which goes wherever you want the signal broadcast to.

This isn't the most aesthetically pleasing network equipment - the window unit has the look and feel of a cheap toaster, and peeking inside reveals an ugly antenna array that the Cel-Fi was obviously keen to disguise.

Looks aside, the unit works as intended. Our testbed was an old, semi-subterranean cottage in the Devon countryside - a lovely place, but one where getting a 3G signal usually means calling from a very specific spot in the south end of the house.

With the Nextivity Cel-Fi RS2 extender, we were able to extend the 3G network to the north end, and freely browse the internet and make calls. It's impressively powerful too, and able to beam the signal through the thick walls.

The signal did drop occasionally, but this was more due to the undulating Devon landscape - and undulating Devon 3G signals - than the unit itself. Our unit was locked to Orange and T-Mobile networks, with other units available for other providers such as Vodafone and O2. This could be an issue if your home or business uses different networks for all its handsets.


Priced at over £450, it's hugely expensive, and there could be some sense in waiting for 4G to be deployed and simply sticking with a landline or Skype for calls. But there are also a lot of businesses - particularly rural iPhone-centric start-ups - that would benefit from the Nextivity Cel-Fi RS2's technology.

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