Yeah, that's what I'm doing and just finished tonight. Still a bit to go but gist is:

1. Follow @SureVoIPLabs
2. Bot auto follows you back if not already following
3. Sends you a DM with a thank you and instructions.
4. You then send a DM like so:

d @SureVoIPLabs my_mobile_number/number_I_wish_to_call

5. Do some tariff checks and fire off a bgapi with 2 or 10min limit
6. Send you a DM back

All free but limited to UK for now. Will be live next week or so.  Full version with international and App auth coming with credit topups via DM too :)

Gav.

http://www.surevoip.co.uk

> On Mon, Jul 25, 2011 at 11:59 AM, Gavin Henry <gavin.henry@gmail.com> wrote:
>
>> Why not bgapi and listen for the CHANNEL_ANSWER event?
>>
> Dealer's choice. You can totally do that if you so desire. It all depends on
> what the ultimate goal is. If you just need to have a few calls hit the dp,
> attempt bridge, then play messages based on failure types then the dialplan
> itself can handle it with just continue_on_fail and transfer apps. You can
> throw in a dp script if you have some specific logic you wish to apply.
> Keeps it clean and simple. However, if you are wanting to do some async
> stuff like real-time status updates, etc. then event socket w/ bgapi
> originates is definitely the way to go.
>
> -MC