Enhanced e-mail delivery to mobile devices

A non-transitory, computer-readable medium containing instructions executed by a processor to perform stages for delivering e-mail, the stages comprising:

• receiving, at a gateway server that controls access to an e-mail server, an indication that e-mail messages are available at an e-mail account associated with a first and second user device of a user;
• storing the new e-mail messages at the gateway server;
• transmitting e-mail notifications from the gateway server to each of the first and second user devices;
• receiving, at the gateway server in response to the e-mail notifications, a first indication of a first battery level in the first user device, and a second indication of a second battery level in the second user device, wherein the first and second indications include device identifiers of the first and second user devices, respectively;
• comparing the first and second battery levels to a threshold level;
• synchronizing e-mail with the first user device when the first battery level meets the threshold level;
• activating at the gateway server, when the second battery level is below the threshold level, a filtered mode for synchronizing e-mail with the second user device, the filtered mode transmitting a filtered portion of the available e-mail messages to the second user device;
• transmitting the unfiltered portion of the available e-mail messages to the second user device when the second battery level is above the threshold level;
• and
• deleting the stored e-mail messages from the gateway server based on transmitting the messages to both the first and second user devices.

A gateway server for controlling access to an e-mail server, wherein the gateway server:

• receives an indication that e-mail messages are available at an e-mail account associated with a first and second user device of a user;
• stores the new e-mail messages at the gateway server;
• transmits e-mail notifications from the gateway server to each of the first and second user devices;
• receives, in response to the e-mail notifications, a first indication of a first battery level in the first user device and a second indication of a second battery level in the second user device, wherein the first and second indications include device identifiers of the first and second user devices, respectively;
• compares the first and second battery levels to a threshold level;
• synchronizes e-mail with the first user device when the first battery level meets the threshold level;
• activates at the gateway server, when the second battery level is below the threshold level, a filtered mode for synchronizing e-mail with the second user device, the filtered mode transmitting a filtered portion of the available e-mail messages to the second user device;
• transmits the unfiltered portion of the available e-mail messages to the second user device when the second battery level is above the threshold level;
• and
• deletes the stored e-mail messages from the gateway server based on transmitting the messages to both the first and second user devices.