Sunday, March 31, 2013

Did you see what I heard?

Spectrogram Pro is a very cool app that plots the spectrum of sounds in real time.  That is, the vertical axis is a graph of how much sound energy there is at each frequency (what we hear as pitch) and the horizontal axis is time.  In the picture above, the left half shows me whistling in the mid-range - it shows up as mainly one bright line.  Then I plucked a single string on a guitar - on the right you see a whole series of frequencies made by this vibrating string.  The lowest one is the note you hear, and all the ones above it are overtones (or harmonics), that give the sound its guitar-like flavor.  You can also see how the upper harmonics decay away more rapidly with time.  I showed this in one of my physics classes where we had recently studied Fourier transforms - this is the fancy math that is used to process the sound wave into it's component frequencies.  The fact that the app is on the iPad means you can take it anywhere, which is very handy.  It's also just plain fun to mess around with.  It costs $2.99.

Friday, March 29, 2013


March 2013:

I finally figured out a way I don’t have to give up my ubiquitous yellow legal pads on which I write notes about everything.  Penultimate for the iPad, that syncs with Evernote is my new toy of the month.  It allows me, with a finger, to sit in meetings, conferences, class, and take notes directly on the iPad and then sync them to existing files on Evernote rather than have them floating around on my desk on different pads of paper.  I’ve been using it in class to annotate syllabi and class notes and it was great at a recent conference because you can even search the handwriting for different categories and notes.

Saturday, March 23, 2013

OK, I realize this is an embarrassingly simple use of the iPad in teaching, but it is one of the best I have experienced in this experiment. I am remaking parts of a course I am teaching this semester as I go, after becoming dissatisfied with how things were going earlier in the semester. That means that I am unusually dependent on notes I have written for class -- usually writing notes is enough to prepare me to navigate through a session without them -- but I also want to be able to highlight them for later revision in light of how the class conversation goes. The iPad, using GoodReader, has been a nice tool for that. A quick glance now and then keeps me oriented to the plan I set for myself and my students and a swipe here and there at the screen allows me to go back later and rework things.

Luddite that I am, this is as good as it gets!

Friday, March 22, 2013

Mapping Apps

One of my absolute favorite uses for the tablet are mapping Apps.  It's the one area in which the iPad has brought me all the joy I had hoped for, and then some. 
Hands down, my favorite is Google Earth--but who doesn't love playing with Google Earth?  I'm hoping to make use of it in some of my environmental courses, where I think it will be a useful way of situating the controversies we talk about in real space. 

After that, I've enjoyed experimenting with several mapping programs that allow me to get additional information about places I was mapping, including satellite and terrain images, and topographical information.  I've had good luck with Maps+, MyTopo Maps, and World Map. 
I am really hoping to be able to use these mapping apps when I visit India to do some guest lectures, but I honestly don't know what kind of functionality to expect in India.  Does anyone have any advice for traveling with the device in this part of the world?


Wednesday, March 13, 2013

Logitech Keyboard Recommendation

I transitioned to a standing desk in my office but use my iPad when I need to sit to work. I frequently needed to type using my iPad and the Apple bluetooth keyboard was sufficient for that. However, I had multiple problems syncing between the keyboard and my computer and then back to my keyboard and iPad.

This Logitech keyboard (K811) solves all of my syncing problems. Right out of the box, I synced the keyboard to my Mac, my iPad and my iPhone. Now the keyboard remembers that it is permanently synced to these three devices and I can easily switch between these bluetooth devices. I highly recommend this keyboard.

App Review: Genius Scan

For the last semester I have been using a handy scanning app called Genius Scan.  Its a free app, simple to use, and has been really useful.  This app allows you to take a poor-quality photo of a document and turn it into something you aren't ashamed to send to a colleague or student.  The app has two primary features.  First, it automatically detects the shape of your scanned document and ensures that it takes on the correct perspective.  For example, when your document inevitably assumes the shape of a parallelogram when photographed at an angle, the app will automatically transform it back into a rectangle.    The second feature is that it automatically transforms your scan into black and white text.  This means that your photo won't look like a photo at all.

The app is very intuitive to use.  It is easy to add multiple pages to a single file.  It is also easy to either email your document or save it directly to dropbox.  The default file is a PDF, but you can also save as JPEGs.

I've used this app on multiple occasions to scan graded student assignments that I want to return electronically.  I've even scanned a few pages of a book to send to a colleague, the though results are not as strong if the book binding causes the pages to curve.