Mobile e-mail is a new technology that lets cellular phone subscribers retrieve messages through a portable device. The idea of providing handsets with e-mail access is not really new: operators have been offering an SMS-based e-mail solution allowing users to send messages through a predefined e-mail address that’s tied with the subscribers’ mobile phone number.
With this service, e-mail is converted into a standard SMS message, often resulting in multi-part messages as a way of going around the 160-character limit. With the introduction of smart phones capable of connecting to a data network via GPRS, MMS mail offered a solution resulting in longer messages and support for attachments.
After SMS and MMS, access and synchronization solutions over GPRS to mailboxes were next. These mobile e-mail solutions may be classified into two types of user experience—“push” and “pull.” Pull e-mail requires users to initialize retrieval by either opening their WAP browsers or sending an e-mail retrieval command via SMS. Slightly more advanced is the scheduled e-mail synchronization application that pulls e-mail to the device every few minutes.
In essence, some user intervention is required to check for new messages in a pull setting, none of which provide automatic real-time e-mail experience. Push, on the other hand, is the term used to describe automatic delivery of e-mail to a mobile device. What makes push work is its always-on connection to a relay server that communicates with the e-mail server and performs “polling” or constant checking for new messages. Once it receives a new message, the relay server pushes it to the mobile device’s inbox, resulting in a more natural user experience since mobile e-mail users are already used to sending out and receiving SMS.