This spring we are re-evaluating our software for the summer excavation season. The iPad was so new last year that we went with what was available and while it worked, it could have worked better. Now we have another whole year of software development with some more sophisticated apps. Since drawing is the most difficult task to learn on the iPad, I am starting with those apps.

The PARP:PS team in Cincinnati will be meeting to start evaluating these apps as a group. The first one that we will look at is a new drawing app named TouchDraw, which has a lot of features that I like, and only a few quirks.

This post is written in the style of a software review but with a specific purpose: for drawing technical drawings in the field. There might be some features that make one piece of software stand out among the others, but if it doesn’t do me any good, I don’t really mention it here.

I will be posting some homework assignments to the group, but they will be different from the assignments from last spring. Instead of tracing a pre-drawn trench plan, I want them to work with the software in the same way as they do in the field: to draw from scratch. That means some measuring and triangulation to get the items where they belong. To make it easy for them, I will ask them to draw their desk and some of the items on it. Here is mine (more difficult than most because of the curve). It isn’t exactly what you would find in the field, all the items are pretty geometrical and not irregular, but it allowed me to learn a lot about how the software works.


The documentation for TouchDraw is pdf based and needs to be downloaded before reading. There is a Quick Reference Guide and a User Manual. The manual is well written and includes screenshots of the features mentioned. Therefore, I did not include any screenshots in this post.


Documents are easily transferred to and from the iPad via iTunes. There is also a cloud option, which reads and writes documents to a Dropbox folder. You can move or copy drawings from the local storage to the cloud directly from the iPad. A unique feature is the ability to save as… so you don’t have to leave the drawing, go to the browser, duplicate the drawing and open it back up to start the next one. Save as… will let you start on the new drawing immediately.

Setting up Scales, graphs, layers

We usually only create a single new drawing from scratch for each trench at PARP:PS. Once the base drawing is complete we duplicate that drawing for other uses. The basic setup for each document is done in the info menu. There we can select the units for the drawing. We use cm. TouchDraw acts more like a CAD environment than a page layout program in that it does not have a page size. Drawings are essentially unlimited in size. This makes it easy to have drawings of various scales, so you might want to make that explicit in the title box for each drawing.

The rules on the graph paper dynamically appear based on the level of magnification, which is nice.

TouchDraw has a freakishly large zoom level. I reached 216,437,286% before I got bored. At any rate, you can zoom to your heart’s content.


The tools are lockable. That is, if you tap on the rectangle tool and draw a rectangle, after that is complete the pointer tool is selected by default. But if you double-tap a drawing tool, it lock that tool until a different tool is selected.

In the tools menu there is a snap to grid option. That appears in most drawing programs and is handy for drawing the scale bar. In the tools menu under the general settings section is a toggle for snap to lines. This doesn’t appear in the documentation but it allows you to snap the ends of two line segments together. The line segments don’t join, but they do connect. There doesn’t seem to be a way to snap the end of a line to the middle of a line segment. Nor is there a way to snap closed shapes, only open lines. Snapping also won’t work if the line you want to snap to is locked.

Also in the tools menu are a couple of useful features in the drawing view section. Easy drag mode allows you to move shapes without fear of moving just one handle of a shape. Crosshairs puts full-screen crosshairs when you touch the screen. These extend all the way to the rulers and are quite useful. The show overlays option puts a heads up display (HUD) on the screen with information on the object you are creating/editing. This feature is incredibly useful for technical drawings, as it allows you to see the size of objects as drawing, but there are aspects of it that can be improved (more on that below).

Adjusting the elements of objects is fairly simple and is surprisingly absent from other drawing programs. Once an item is drawn you can select the adjustment menu item and change the position, width and height of the object. There are three oddities to this behavior. One is that I find the precision to be much more than I need. I don’t exactly need to know that the width of my rectangle is 0.89493525362219 cm. When making a technical drawing, I sometimes draw the rectangle at any size, call up the adjustment box, and hand edit the dimensions. In order to change that number to, say, 1.95 cm, I have to hit the delete key numerous times to get to the start to type in my dimensions. The second oddity has to do with the HUD feature mentioned earlier. For example: when you draw a line you see the line length and angle. But once you draw the line, you can never see the line length again. You can see the start and end points in the x/y grid on the HUD, but not the length. When you call up the Adjustment box you can see the overall width and height of the rectangle that the line occupies, but you can’t change the line length. The last oddity is that the position given for the object is always the upper right corner. There are times that I would like this to be the center position of the object, but maybe I am being picky.

There are an endless number of things that one might want to do to a vector object and various drawing programs have different methods for allowing access to those tools. Most of them use a contextual menu for items like duplicate, copy, paste, delete as well as some other more advanced functions like insert points, change to paths, etc. The standard way to get these is to hold your finger to the element for a second or so and then lift up. My experience is that this works only some of the time. But TouchDraw has a contextual menu item in the left menu bar that calls these commands without the finger trickery. That itself will save lots of drawing time.

New to us will be the Group option. We didn’t have that last year but the ability to group elements so that we can move them all at once is a good feature. Likewise the ability to lock and unlock. Last year we had to make sure items were on different (locked) layers if we wanted to avoid tapping on them inadvertently.

Another incredibly useful feature is the function lock (from the tools/general menu). This acts like a shift-constraint in most desktop programs. Activating it will keep the proportions of an item the same while scaling, and lock the direction of lines to horizontal or vertical.

The last great feature worth mentioning is the library. You can save graphic and text elements to the library for reuse. For example: elevation marks, title boxes, that sort of thing. This is something that we wished we had from the beginning.

Some of the terminology might be confusing. The handles that change the direction of a line at a point in Illustrator are called direction lines. In TouchDraw they are called quadratic curve segments. This took a little while to get used to but it is well documented in the User Manual.

The color picker is handy but I would also like to be able to store colors for reuse. Some other drawing apps have that feature and I was looking forward to using it this year. TouchDraw won’t allow that.

Auto Save

One of the big questions that I have is “what happens when the app crashes.” Some apps save the data anyway, some don’t. TouchDraw didn’t crash on me during testing, so I have no idea.


The documents can be exported as jpeg, pdf, svg, png, and visio.

Whether exported as pdf or svg, the documents open up in Illustrator just fine for additional editing. The layer structure, however, is not preserved in either format.