

Missed call - jitbit
https://en.wikipedia.org/wiki/Missed_call

======
gt565k
In my home country of Bulgaria, we used to do that all the time.

It works because most phones are pre-paid. You don't have a monthly bill.
Instead, you preload $10 - $20 into your SIM, and you can text at $0.20 per
SMS or talk at $1 per minute. Also, only the person that initiates the call or
SMS pays, the receiver is not charged anything.

You'd still need at least a balance of $1 to initiate calls, so when people's
balances get low, they only call people and hang up immediately (we call that
clicking / buzzing).

Essentially you make plans to meet somewhere or go out, and you click / buzz
the other party when you are ready. It is generally understood that if you get
a click / buzz, you should look around or call that person back if you have a
higher balance ;)

Also with the preloading SIM card payment model, you can essentially have a $1
balance on your SIM card for a year, and receive calls without paying
anything.

------
stegosaurus
In poor countries? Like the UK or anywhere else where missed calls are free?

Me and my friends still do this. If one person has an unlimited or cheap
contract then the person without sends a missed call and is called back.

I am not sure how well this would work in the US as apparently you can be
charged for inbound calls there.

~~~
greenyoda
_" I am not sure how well this would work in the US as apparently you can be
charged for inbound calls there."_

Right, in the U.S. you're charged for "air time" on both outbound and inbound
mobile calls. However, the trick would work with land-lines, and is especially
useful when one party has a calling plan with flat-rate monthly billing and
the other pays per-call. I had some family members who did this many years
ago, long before there were mobile phones.

Answering machines (for land lines) are also designed to exploit the "missed
call" trick: if I call my home answering machine to remotely retrieve my
messages, it will answer on the first ring if I have messages, otherwise it
will answer on the fourth ring. Thus, if it rings twice, I can hang up, having
learned that I have no messages without having paid for a call. (Even if I'm
calling from a mobile phone and paying for the call, I've spent much less time
to find out that I have no messages.)

The only problem with this scheme is that it's somewhat unreliable. The "ring
tone" that the caller hears is generated by their local exchange, and doesn't
exactly correspond to the ring on the callee's phone, which is generated by
the remote exchange. So the caller may hear a ring tone and hang up before the
callee ever hears a ring. (At least that's the way it works in the U.S.) So
it's probably more reliable to hang up after the caller hears two ring tones.

------
a-dub
Back in the '90s, we used to pass messages around from payphones for free by
stuffing them in the name recording on automated collect call authorization
systems.

We'd call the 800 number or dial 0 to setup a collect call and when the
machine would prompt for a name, we'd stuff the message. The end result was
the recipient receiving an automated phone call that would announce: "Hello.
This is Pacific Bell. You have a collect call from WEREATTHEBEACH. Press 1 to
acc..."

------
Psyonic
So this is what people did before Yo...

