Here's an overview of the apps and functionality you can tap into to use your Nokia 3650 as an on-the-go mobile office. I'll be the first to admit Series 60 lacks a bit in this area because smartphones aren't as easy to enter data in as a PDA-model type phone such as the P800 or a Palm phone, however if you want to keep track of what's going on in the office and keep in touch, it's a great compact solution.
First... - The first step is to get yourself a decent sized MMC card for documents and such, as well as make sure that you have some sort of plan for GPRS networking so you don't go broke with per kilobyte charges. If you don't start here, you're not going to be really able to take advantage of the stuff below.
Series 60 phones have built in Contacts, Calendaring and basic To-Do lists. Once you get the PC Suite installed, you can import your contacts and calendar from common corporate PIM apps like Outlook and Lotus Notes/Agenda and sync later, etc. It's not Palm Desktop by any stretch, but it'll work. Also built-in but often overlooked apps are the Calculator (with a virtual tape, way better than Windows calculator) and the Converter which will allow you to convert from anything from different monies to measurements such as weight, distance and temperature - very handy if you're in another country (believe me).
S60 also includes a Messaging application out of the box which will allow you to read your POP3 or IMAP email from your phone. It's not the greatest email client ever made, but it will allow you to read your email and any attachments. The main problem with the email is that there's no way to schedule it to download new mail (the 6600 will fix this). Thus for the 3650 you'll have to go buy an app which fixes this called ActiveMail. You can set up schedules for your different mail boxes and it will connect on that schedule and download new mails in the background for you, just like your desktop email app. Another solution is ReqWireless' proxied email client called Email Viewer. This is a Java application which will allows you to view your email remotely. This is a very good option as you can conserve bandwidth by not having to download big attachments or Spam unless you need to, and the app also includes a Spam filter, and integrated file viewers as well. This app, however, is a service so you have to rely on this company's servers to do the proxying, but it seems like a really good deal.
To keep up with the latest news on the road, you need a decent web browser. Though the 3650 includes a serviceable WAP and XHTML-MP browser, it doesn't do what you need when you want to read normal web pages. So you need a "real" web browser. What ever you do, don't buy Opera for Series 60, though when it does work it's fantastic, it doesn't work reliably within the limited memory constraints of the 3650's 3.5MB RAM. There's only two real options for browsing on the 3650, that's the fantastic Doris Web Browser, and again, ReqWireless' proxied browser called Web Viewer. Doris is the way to go. It's fast and allows full-screen browsing. It doesn't try to display the web pages exactly as they are designed, but it rarely fails on news sites and other content-heavy sites. And it takes up no memory what so ever. Great app.
There's a few different options for chatting from your phone, but I'll just mention the best few. First is the pretty amazing Agile Messenger which, believe it or not, is a free app. This will allow you to keep in touch with anyone back in the office who uses Yahoo, MSN, AOL or ICQ. It's a well done app. Another app along these lines is TipicME, a Java based app which uses Jabber as its back end to connect to the major services (I suspect that Agile does the same, but I'm not sure). The other option is only if you're a real geek (like many of us on #mobitopia) and use IRC. The absolute best application - quality and functionality - for the Series 60 is Wireless IRC. It connects to IRC flawlessly, has great alerts (with little bubble icons, even if you've switched to another app) and allows for seamless switching between IRC channels and private conversations as well as send/receive files over DCC. It's an insanely well done application. Get your office on IRC and you will be completely connected all the time with this app.
One of the important things to be able to do when you're on the road is to be able to check out the documents that are sent from your coworkers. Thankfully, there have been several new software releases which will allow you to view Microsoft Word, Powerpoint and Acrobat (PDF) documents as well as a basic Text Reader. Let's start with the last first: ReadM is a fantastic (and free) text reader which supports plain text, Aportis Doc and gzipped text files. If you want to check out a PDF document on the road, you can use PDF+ by mBrain Software. And Mobility Electronics has released QuickWord and QuickPoint for MS Word and Powerpoint files. I've tried the trials on all these apps and they work as advertised - no need for file conversion.
Finally, there are other apps which you may find useful in a pinch when you're out of the office. Since PDFs and Word docs can easily run into multiple megabytes, you'll need a decent MMC card to store all these docs and an App like FExplorer to find them. Though downloading a 5MB Word doc over GPRS might be a bit painful, with Infrared and Bluetooth connectivity, you can use your 128MB MMC as a storage medium for important documents on the go. Also, an app such as Mobile Fax by BiTween software will come in handy as well. You can send, receive and view faxes from your 3650, probably easier than on your PC. Also there are online Sync services such as MightyPhone which will allow you to back up your info via SyncML (a free app that you need to install, it comes on the CD on your telephone or via Nokia's website) and check/manage your info via the web or a custom PC client.
So, like I said, most of these apps are just for just keeping up, rather than having a full-on mobile office which might be more possible for PDA-type phones. And downloading a 4MB Word doc over GPRS isn't the funnest or cheapest thing to do. But these apps will just get better - once all the apps get to the level of quality as Wireless IRC, the Symbian/Series 60 phones will be a force to be reckoned with, if they aren't already.