I regularly search itunes for free math apps that I can use in my high school classroom. If I see one I like, I download it, check it out, try it out and if it is good, I add it to my list and then figure out how to integrate it into my classroom. emath 1 is a bit different because it is the English version of a Finnish high school math textbook. It is on functions and e2quations and is interactive. The site says the company plans to publish more books throughout the year.
Although the labeling of subsections is not what we are accustomed to, it works well. The chapter begins with a prerequisites, a reflection and a short history section. In the reflection section which is more of a lets do a quick check, they use hearts, diamonds, spades or clubs, just like on playing cards, instead of variables. There was also an interactive number line.
In the actual section, the material is introduced in small chunks using solid mathematical terms with examples. I do like the fact it gives many different examples that I do not usually see in regular textbooks such as 3.44 = 344/100. It has other examples which show a different way of doing things such as 5% of 15 is shown as 5/100 * 15 rather than using decimals.
The introduction does state that this can be used as your main book or as a supplemental. Since I work with ELL students, some of the wording in it might be a bit harder for them to understand but if I carefully select parts that would reinforce their learning and use it as supplemental material, it would work in my classroom. I plan to keep an eye out on them over the year for new books.