Q: I liked the old data format where everything was in columns! Why did you change it?!
The new data format was implemented because of the inability for iOS devices to poll sensor data at specific intervals and at exactly the same time. How quickly the app samples is based on the current processing load on the device so if you want it to sample as fast as possible, close all other background apps. For the fidelity of the data, I also changed the format so each row of sensor output has it's own timestamp. As you can see there is a small difference in time between when one sensor and another are sampled. I agree, the old version was much easier to work with since I could just open it with MATLAB or Excel and have everything ready to go. This new output format is much, much more reliable and it's not that much harder to work with in MATLAB and Excel. For Excel, you can sort the data in the table by sensor and then by timestamp and it will be just like the old version! For MATLAB, you can also sort it. Unix-based operating systems have it even easier: you can just grep the file for the sensor data you want and it will be just like the old format. For example:
cat INPUT_FILE | grep ACCEL > accel.txt
v1.0.7 updated the app for iOS 7.0, fixed French localization, and fixed accelerometer axes.
v1.0.4 Code architecture was redesigned and GPS logging functionality was added to the paid version.
v1.0.3 Upgraded the paid and free versions of the app to use iOS 6.1 functionality.
v1.0.2 Removed ads from the paid version of DC and fixed some text in the email message for both applications.
v1.0 adds a "Rate Us" button to the app.
v0.95 fixes bug on certain devices which causes recording to crash the app.
v0.94 gives the user the ability to select the sampling frequency.
v0.93 will fix issues with the new format for the outputted file.
v0.92 brings a fix for older devices which don't have a magnetometer and a new format for the outputted file.
v0.91 Initial Release.
For any support or inquiries, contact: woznych [snail] gmail [period] com or via Twitter: @Data_Collection
I'd also love to hear about any interesting things you are using the app for!