**Bottom Line:** Not at all interactive, but may be helpful as a reference guide for students currently taking a geometry class.

The number of educational apps for junior high and high school students is still quite limited, especially compared to the huge number of apps for younger children. When I first saw this app, I was excited about the possibility of a good app for my math-loving 10-year old to learn more about geometry in an interactive way.

Alas, this is not the app. Geometry Stash is a reference guide developed by Apparent Etch, and not at all an interactive teaching tool. It contains 54 theorems, postulates, and corollaries listed in alphabetical order. The user can scroll down through the list, or search using the search box at the top of the page.

When one is chosen, the theorem, postulate, or corollary, with an illustration, is displayed. On the Hypotenuse Leg Triangle Congruence Theorem (HL), for example, the theorem is “If the hypotenuse and a leg of a right triangle are congruent to the hypotenuse and a leg οf another right triangle, then the triangles are congruent.” Underneath this theorem are two right triangles, labeled as triangle ABC and triangle EFG. On the right side of the screen, the theorem name is summarized as Δ ABC ≈ Δ EFG.

As far as I could tell, the math was accurate in this app, though I didn’t thoroughly check all 54 as my brain started to seize after about 20 (it’s been awhile since I’ve studied geometry.) As a study guide, alternative to flash cards, or a quick reference guide for a student doing homework, this app is likely to be useful. It also may have been useful when I studied for the GRE a few years ago.

However, it is definitely not a curriculum source, and cannot be used apart from a curriculum. The user needs to already know how to actually apply these rules. Also, what good is geometry without the true joy of a theorem proof? Even for those who find such work dreadful, the process of a proof definitely aids in understanding the concept.

I was hoping to at least have some space to manipulate shapes to prove the theorems. In the Alternate Interior Angles Theorem, the user could use a tool to measure the angles to see that they are congruent, as well as try to disprove by changing the angle of the transverse line and measuring the angles to verify congruency. Similarly, in the Chord Chord Product Theorem, being able to measure the line segments as well as move them to measure again would make the app interactive and much more useful for understanding the concept.

It would also be useful to have a writing function, to allow the user to make notes on each page. Even a flash card function would make it better. Currently, the name, written explanation, and the letter/symbol summary are all listed in the same view.

While it is optimized for the iPad, there is a large bar across the bottom in landscape mode. In portrait mode, the bar is much smaller. Regardless of size, the only purpose for the bar is to show the theorem when selected from the list. If the list shows just the names in alphabetical order, tap the black bar to show the theorem. If the screen shows the theorem, tap the bar to hide it and show just the list. This feature is nice, but a better design would make the app a little more visually pleasing.

Is this app worth downloading? If a student already has a class with a standard textbook, then it might provide a convenient method to quickly find the required information to complete homework, as opposed to having to use the table of contents in a big textbook (which, of course, I had to do back in the old days.)

If a convenient, quick-reference guide for theorems, postulates, and corollaries sounds interesting to you, Geometry Stash will probably be useful. I have to admit that it was also enjoyable for me to read through the information and remember exactly how much I like geometry.

Although it's more portable and doesn't require an internet connection, is this app any better than a webpage that might provide the same information? As it stands, without any interaction or better graphics, probably not.

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If you would like to download Geometry Stash please support Smart Apps for Kids by using the links provided. Thanks for your support!

iPad/iPhone ($1.99): U.S. Canada Europe Australia

*This review was completed by Heather Hetler, who works as an elementary school SLP and is a full-time graduate student in Speech-Language Pathology. smartappsforkids.com was paid a priority-review fee to complete this review in an expedited manner.*

**STAR GUIDE**

**Five Stars:** The best of the best. We've reviewed, featured, given away, and tested thousands of apps and only given 19 apps the full five stars.

**Four-and-a-half Stars:** One of our Top Picks. We highly recommend this app.

**Four Stars: **Just a notch below the best. Recommend.

**Three-and-a-half Stars: **Has enough strong points to recommend if you have a specific need is this area. Definitely take a look.

**Three Stars: **Worth a look, but only worth downloading if it targets a specific educational target you are looking for.

**Below Three Stars: **Not recommended.

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