Use a Wi-Fi network whenever one is around. When you are in transit, such as on a train, you can manually switch to GPRS access. The downside is that GPRS access is slower and much more costly than Wi-Fi access. The theoretical speed of 40.2 Kbps is not achievable in the real world?expect performance of closer to 30 Kbps for activities such as web browsing.
Since GPRS is much slower and costs more, turn off image loading in your web browser when surfing the Web. This causes the web pages to load faster and saves you money.
If your cellular provider supports a compressing proxy (See Section 7.5, previously in this chapter), give it a try. Such a proxy server can increase speed and reduce your bandwidth consumption.
GPRS speed is acceptable for checking email, but it is advisable to configure your email client to download message headers only: if someone sends you a multi-megabyte attachment or even a long message, it could take a long time to download and use up your bandwidth allotment. Use an IMAP mail server and client if possible, as IMAP is particularly well-suited for high-latency networks. You can then decide on a message-by-message basis whether you want to view the message body and/or download attachments. You should also install a spam filter in your email application to avoid downloading huge junk emails. Many email clients include some spam-blocking features, and typically analyze the email headers (rather than the body of the message) to determine whether a message is spam.
Lastly, make full use of the SMS feature. Sending SMS messages may be cheaper than making a voice call. You can type them with the keyboard on your notebook and they will be delivered quickly. SMS is also more discreet than talking on the phone!