If you do not have access to the network, there is a feature that can make it easier to read your e-mails called offline browsing, thanks to it you can access your e-mail platform without need to connect allows you to send mail, save connection costs and avoid spending the device battery.
If you use Gmail
You can download the "Gmail Offline" extension when you're online using Google's system.
You can also search for "No connection" option on the "Settings" menu, as long as you use Google Chrome.
This feature only serves to check the emails you've received, but you will not be able to see the new emails that come to you.
the Microsoft Platform is also an option without the Internet: "Work Offline" Outlook 201
To enable the system, just select that option on the "Send and Receive" tab ". You can re-enable the connection on the same button.
If you're using the app, select the "Offline configuration" option and select the option "Enable offline access."
It is worth mentioning that you will not be able to send or receive mail  Twitter and  Google+ .