The NumWorks graphing calculator

I can testify that children taught operations by hand will absolutely have as much problems with decimal orders of magnitude as those taught using calculators. Order of magnitude (well... Sense based validation of results) is a different and mostly independent, unrelated, teaching. They can be quite conflated.
Take for example decimal comma positioning in manual multiplication. It will be placed by a calculus on operand comma position, not on estimated expected order of magnitude of the result. And learners will stick with it.