If you're anything like most city dwellers, your apartment building has a call box that'll let you buzz a guest inside by pushing a button on your phone. Unfortunately, most city dwellers are also forced to designate only one phone number for the apartment buzzer to call. Here's how you can get around it with Google Voice.
OK, can we put a call in to tech designers everywhere? Before you get working on the iPhone 5GSX.2.9, figure out a way to redesign apartment call boxes so they can buzz out-of-state numbers, multiple phones and anything other than a landline. In our last three apartments, each of our building's call boxes had one of these annoying restrictions.
Luckily, there's a work around for all three that doesn't involve throwing away money to a phone company. Gizmodo shows us that you can get it done using Google's free VOIP service, Google Voice.
Once you sign up for Google Voice, you'll be assigned a unique phone number in whatever area code you choose, so it'll match the local area code. Give that one to your landlord to program in the building's call box, and make sure Google Voice's settings are set to forward that call to your main number (probably your cell, right?).
From here, you'll need to mess around a bit with Google Voice's settings. Once you buzz yourself from your building, you'll be able to save the apartment's call box as a new contact and, using Google Voice, assign that contact to a group that can ring multiple phones at once—all you need to to is add each of those lines for forwarding in Google Voice.
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This doesn't work everywhere. I tried it at my last apartment. Calls never went through to my Google Voice number, and I had to get them my cell number instead.
Not all phone services can place calls to GVoice, it seems.
I live in a building where this could never work either. I have no landline service, but am required to waste the electric outlet for a cordless phone just to answer the door. The box downstairs doesn't actually dial anything, it rings the phone line directly the same way the phone company would, so on mine it has to power a dead line to do so.
This is what I use and it works great! I gave my landlord my Google Voice number because my cell number wasn't a local area code. The only thing is that I cannot use the feature where the caller annouces their name before I can decide to take the call or not - not a big deal.
This would be great if Apple weren't cockblocking the Google Voice app on iPhone for purely anticompetitive reasons. That, and the inability to port my number to GV. If it weren't for those things, I'd be able to cancel my voice subscription and have a data plan only, and barely use even that since I'm around wifi for 99% of my life. Even though GV isn't true VoiP, you can hook it up to other VoiP solutions like Skype and have a perfectly awesome voice service that cuts the telecos out of your life without sacrificing any of the features.
Hurry up with the number porting, google!