Quick, how many miles in a light-year? Or, how many light-years in a mile? Or, what is the current exchange rate between the US dollar and the Japanese yen? If you need to do a quick conversion between units, then this app maybe just the one for you or your classroom.

##### App Overview

The Convert Units app is a conversion calculator. The interface is clean and intuitive. One nice feature is the ability to set an amount and a unit and then quickly scroll through the conversions. For example, you can input 50 miles, and then just scroll through the conversions from angstroms and microns to light-years and parsecs, and everything in between. Input can be positive or negative integers or decimal numbers.

Conversion Categories:

• Area (sq ft, sq yd, sq mi, sq mm, sq cm, sq m, sq km, ac, ha)
• Numerous currencies with live updated currency exchange rates
• Data (bit, B, KB, M, GB, TB)
• Energy (BTU, ft lb, erg, kW-h, W-h, kg-cal, cal, kg-m, n-m, J)
• Force (N, dyn, kg, lb, pdl)
• Length (A, m, mm, cm, m, km, in, ft, yd, mi, nmi, AU, ly, pc)
• Mass (oz, lb, S/T, L/T, mg, g, kg, st)
• Power (BTUS/min, ft-lb/s, ft-lb/min, hp, w, kw)
• Pressure (psi, pft, at, bars, inHg, cmHg, kg.m/m2, pa, inAq)
• Speed (ft/s, ft/min, mpmin, mph, m/s, km/min, km/h, kn)
• Temperature (F, C, K, R)
• Time (ms, s, min, h, d, wk, y)
• Volume (gal(US), gal(Imperial), L, ml, tbsp, tsp, fl oz, cu yd, cu ft, cu in, cu cm, cu m, dram, pints(US), pints(Imperial), cup, qt)
Join for full overview
##### Instructional Ideas

• This would be a very useful app to have available in any science classroom
• The app could be used to help learners gain an intuitive feeling for how different units compare. For instance, how big is a light-year or how do an ounce and gram compare?
• Conversions in length can lead to some very small or very large numbers and may make an interesting review or learning opportunity of scientific notation
##### Classroom Considerations

The app is still useable without the in-app purchase (.99) to remove the ads. The adds take up only a small amount of the screen and change quickly. This means that they may not be an issue if you use this app as a quick-reference tool. If, however, you are using it for longer blocks of time, or your students are easily distracted, it might be worthwhile to do the in-app purchase.