Mobile Phone Rate Arbitrage Using Free Mobile To Mobile Minutes
About two months ago I came up with the following idea to lower mobile phone bills.
In the United States it’s common to select a cell phone rate plan based on the number of ‘anytime minutes’ which are typically weekday daytime minutes. If you go over your allocation, the extra minutes are quite costly, and one can rack up a really big bill of hundreds of dollars if one is not careful.
Many carriers in the US offer free mobile-to-mobile minutes, where callers on that carrier can call all other mobile phones on that carrier without using up anytime minutes.
My idea is to modify a mobile phone so that it can be connected to an unmetered conventional or VOIP phone line. The phone could be programmed to answer calls, give the caller a dial tone so they could type a phone number and then dial that number over the landline or VOIP phone line. Once the called party picks up, the calls would be conferenced together, and the mobile caller could talk with the remote party for free forever, no matter the day or time of week.
Think of this as similar to a calling card, but with a cap on the charges. For example, a Vonage line is $24.95 a month and an extra mobile phone line through AT&T is $9.95 a month, plus taxes and service charges, for a total of about $20 a month. So, for $44.95, one could have unlimited anytime minutes on a cell phone. The carriers charge much more, about $99.95 a month per phone, without the taxes and charges included. Those charges probably push the total to $125 a month.
The cost savings of my idea are even more substantial if a family has several phones, as one modified phone could serve multiple phones out in the world. If the modified phone is busy, the caller can hang up and dial directly, using up plan anytime minutes. But a lot of the time, the modified phone would be available to cut minute usage.
The called parties would see the caller ID value of the conventional or VOIP phone line, not the number of the phone in the hands of the caller. This might be an advantage, since conventional and VOIP lines support name display as well as number display. There might be a software solution to this issue, to optionally allow the originating cell number to carry through to the called party instead.
This cell phone arbitrage might be possible with just a software application on a fully open phone platform. I could see software being written that would answer calls only from pre-programmed numbers, and then use a VOIP application on the same phone to place the outbound call. If the phone is left at home or at the office where there is WiFi, the VOIP call can go out over the WiFi connection.
I suspect there are no mobile phone platforms out there today that are open enough to permit this. It just seems unlikely an application can be written to answer the phone automatically and verify the user is authorized before placing an outbound call. But I suspect there are development cell phone platforms available that are fully programmable. I would imagine these being used by companies for example building home automation systems where the homeowner might want to call in to turn on the air conditioner via the mobile network.
Mobile carriers could block my arbitrage idea by requiring phones to be moved regularly. If they sensed one phone was being used in one place all the time, they could discontinue free mobile-to-mobile minutes for that phone, ruining the cost advantage.
The rate arbitrage works for receiving calls as well. Just ask your contacts to call the conventional or VOIP number instead of your actual cell number. The modified phone could be programmed to answer inbound calls from the conventional or VOIP line and then dial your cell phone out in the world using the modified cell phone to carry the call. Then, when you pick up, the two calls are conferenced together. If the modified phone is in use, the inbound call goes straight to voicemail. Sadly, I see no way for call waiting to be implemented, unfortunately, unless two modified cell phones were used. Then the second modified phone could be used to place another call to you in the world, and the call waiting feature on that phone would activate and you could toggle the two calls. The two modified phones could collaborate via WiFi with each other.
The advantage to running most calls in and out of a conventional or VOIP line is that that line can also be used conventionally when one is near that line physically. It could be a normal home or office line.
I like this rate arbitrage idea, but I have no plans to pursue it. I don’t know enough about phones to attempt it, and I think this idea will have a lifespan measured in just a few years. I think all mobile phones are headed towards unlimited pricing that’s affordable. Once that happens, there will be less reason to work with extra phones. However, I would like to see a discussion develop about this idea, and I’m open to working on this idea if it can be shown to be long lived.
