Last year we took a look at Postifier, a device that sits in a mailbox patiently awaiting any deliveries and alerting users on their smartphone when something arrives. Because Postifier relied on Bluetooth technology, range was limited to around 100 ft (30 m), but a new product called Postybell extends range to "any distance" by relying on GSM technology.

Aimed at those for whom a trip to the mailbox isn't just a short stroll to the end of the driveway, Postybell consists of a proximity sensor and a GSM module. When the proximity sensor detects movement in the mailbox, the GSM module calls a specified number, which can be a mobile phone or a home phone. Of course, the GSM module will require a local SIM to work, which is one of the downsides when compared to competitor devices that use Bluetooth or Wi-Fi.

With the use of the companion Postybell app, users can receive a warning when the Postybell battery is running low, forward alerts to different numbers or email addresses, manage multiple Postybell devices, and log mailbox activity. Currently, only an Android app has been developed, but the Postybell team is planning to develop an iOS version.

Measuring 85 x 42 x 12 mm (3.35 x 1.7 x 0.47 in) and weighing 50 g (0.9 oz), the Postybell is powered by a 400 mAh lithium polymer battery that should last for up to 2 to 3 months before requiring recharging. Recharging is via USB, with Postybell also being offered with the option of a solar battery that attaches to a mailbox, and a portable battery that can be recharged at home and attached to the Postybell when it runs low.

As well as keeping tabs on your mail deliveries, the Postybell team suggests the device could also be used to send an alert when someone enters a room or opens a drawer or cupboard they're not supposed to.

Like the Postifier, the Postybell team is hoping to get their device into production with the help of an indiegogo crowdfunding campaign. But unlike the Postifier, they'll be hoping to reach their goal. Postifier fell well short of its US$30,000 goal, and the Postybell has set the same target. The minimum pledge level to put your hand up for a Postybell is $40, with an estimated shipping date of August 2014 if everything goes to plan.

If things do go to plan, future upgrades slated by the team include adding a camera to send images of new mail, and adding heat, humidity and gas sensors to extend the device's capabilities.

The team's video pitch can be viewed below.

Source: Postybell