I've been hard to work for the past month on my next WP7 app. It's called Whiskers and its a password keeper. I wanted to develop a password keeper that accomplished the following few goals:
- Is Simple
- Is Secure
The simple part is, well, simple. Metro UI, clean, appropriate iconography, and features that simply "get to the facts, ma'am". What Whiskers does best right now is store your passwords and other important data easily. What is missing are features such as backup, import, export, etc.
The secure part has been a wrestling match. First, I wanted the data to be encrypted securely. I went through several options and iterations of implementations and finally settled on the built-in Data Protection API (DPAPI) in Windows Phone 7. The API safely and securely encrypts any type of data and does so in a way that the data may only be decrypted on the very same device. By using the DPAPI, I don't have to store any key data, salt values, or other private encryption bits that could be sniffed out of my .xap or from Isolated Storage data.
The second part of security is leaving out the need for application permissions such as Data Services. For me, any application, especially one the stores my private data, should have very good reasons for the need to access the Internet. Whiskers does not and this should give anyone confidence that their data isn't being sent and stored someplace out in the ether. Accomplishing this was full of compromises.
The first compromise was leaving out a Mango feature that I thought would be useful and that is pinning a tile to the Start screen. I implemented the ability to pin any one of your secrets to the Start screen. I later pulled this feature because usage of the ShellTile namespace requires the application to have the Data Services permission. Why? Because a ShellTile has a Uri property which means the tile could redirect to a URL somewhere out in the ether.
Other compromises deal with the whole, import, export, backup and save to the Cloud features that many people ask for. Again, in order to feel that this app is secure and isn't sending your private data somewhere out into the ether, I decided to leave these features out that way I can leave the need to add the Data Services permission to the app.
In the future, I'm considering a pro or plus version of the app that would enable Data Services and allow you to use the Cloud. This would go against my two primary goals for Whiskers but then again, this would be a different version of the app altogether so I guess that is ok.
I hope to wrap up this first version of Whiskers soon and submit it to the Marketplace. Like my previous apps, I'm going to make this free and free from Ads.
So I made Luminance. It's a little icon that sits in the OSX menu bar on the right-hand side where all the other system-tray-like icons sit. Here I can click on it and know exactly what my brightness level is in percentage of full brightness is for all my active displays. I can save the current brightness level and then later recall it. I can also change the brightness level of any active display. This solves my problem. Now I can change my display brightness at any time without fear of being able to return to the saved and calibrated display brightness level.
I've submitted Whiskers the password keeper to the WP7 Marketplace. I think I began working on this last month sometime, after I finished up TeaMate. This app was far more involved than the previous two. There are a total of 17 pages (views) and close to 2,000 lines of code. The .xap may come in at a scant 351 KB but there are countless hours spent putting this application together.
Whiskers is a pretty straightforward password locker. You create an account, give it some details, and its safely stored until you need it. Accessing your information is pretty fast and easy with all the details available just about in one screen. There's even a recent page which keeps track of what you've been accessing lately and displays those first.
