Change your passwords…all of them.
First, there are the obvious ones. With my Android phone, the core communication applications (Gmail, Contacts, Voice) all went though my Google account, so with a quick change of the Gmail password, my email was no longer getting pushed to the phone and new data would no longer be synced. However, with the abundance of apps that are now available, the number of usernames and passwords continues to grow, so I ended up changing dozens of passwords (not a bad thing in the end). This ranged from my Groupon account to my Twitter account. Since each app often remembered my username/password (convenient when I have my phone in hand), you would be wise to change your password on all of them in case the finder of your phone wishes to take advantage of the new account access.
Find your phone and/or remote wipe it.
To my surprise and disappointment, when I reported my phone lost/stolen, I was told that they (Verizon Wireless) had no way to wipe the phone remotely. For iPhone users, you can thank Apple and Steve Jobs for giving away the Find My iPhone for free (previously a paid feature with MobileMe). However, you’ll want to make sure that you have the app installed prior to losing it, or else you’ll be in the same sad situation of having no way to wipe your data remotely. The same applies to Android devices and a good free app to consider is Lookout Mobile Security. With the free version, you can locate your phone on a map and sound a loud alarm. With the premium version, you’ll have access to the remote lock and wipe features.
So, one possible upside to losing a phone is that you do get a fresh start. Although that means you have plunked down a hefty sum for a new smartphone, chances are you might have taken the opportunity to try something new (I went with the Droid Incredible 2) and your phone will have that fresh out of the box scent and more importantly, a factory reset performance that will likely be faster than whatever speed you had gotten accustomed to with your old phone. With a quick click of Backup Assistant (Verizon), restoring through iTunes (iPhones), or running a different app such as Lookout on another Android phone, you can restore contacts, and depending on the application, other important information including previously downloaded apps. Rest assured that your profile on either operating system will remember which apps you have paid for, so you’ll never have to pay twice for an application.