With an iPhone on my leg (in airplane mode, of course) I recorded the takeoff roll and ascent to about 1,000 feet in a fully-loaded regional jet. The raw data was acquired every tenth of a second, and the graph shows a five point moving=20 average of the relative changes (in g-s) of the X, Y, Z, and norm of these values. You can clearly see the takeoff roll starting (at about .3g) and the rotation and ascent. Watch this space for measurements of turbulence, light to moderate.