Simple data entry: Type the (temperature / percentage / pH-level / other number) and just press "Add" to log the data now. If you want to log it at a different time, long press on "Add".
Sophisticated prediction: Uses a MCMC ensamble sampler to extrapolate the data. This automatically handles errors in the data and provides the most likely prediction, including a 95% confidence interval.
Saving data series: If your data series is long, you can save it under a name and come back to it at a later date.