Using High Accuracy GPS with Mobile Apps

There are times when the built-in GPS simply isn’t good enough for your Android or iOS app. Built-in GPS is good for finding a general location of a geographic feature such as a pond, field, or parking lot. If you need to locate a specific parking space, or a geographic feature within a field, or an inlet to a pond then you’ll need much greater precision of a commercial GPS unit.

Examples. Here is a more specific example to illustrate the concept. Let’s say the application users are mapping insect infected trees in a densely forested urban park. If you are using a smartphone GPS, with an average accuracy of 30+ meters when standing under the tree cover, the latitude/longitude coordinates may end up being unusable for future follow-up because there are dozens of trees within a 30+ meter radius. If you are using a commercial GPS with sub-meter accuracy you can have a much higher degree of certainty that someone will be able to locate that exact tree again.

I’ve seen entire days’ worth of data collection get thrown out the window because of significant location inaccuracies caused by using smartphones and dedicated hand-held consumer GPS units that are well known to outdoor recreational folks. I’ve accidentally sent a backcountry trail maintenance crew to a totally wrong location (they got really mad). All I had was a smartphone GPS and my location coordinate was over a thousand meters off even though the Android Location API returned an “accuracy” value of less than 50 meters. Oops — that’s the difference between precision and accuracy.

Good news. The good excellent news is there are small, handheld commercial GPS units that you can tether to your smartphone via Bluetooth such as the Trimble R1. Units like the R1 are able to override the onboard GPS and when configured correctly work just fine with the browser’s JavaScript-based Geolocation API or native iOS/Android geolocation.

The only downside can be cost. Some of these commercial units cost several thousand dollars and that may be outside the budget of many organizations.

Surprise, Surprise. I spend a ton of time talking to customers about this topic. Many people are very surprised because they regularly use GPS fitness tracker apps or Google Maps and the location information almost always seems very close to reality. The hidden trick is these apps use proprietary software algorithms that attempt to slightly improve accuracy, minimize location fluctuations or even intelligently snap your location to geographic features such as roadways, buildings or trails.

When you are building a custom mobile application, you will be forced to deal with raw, unfiltered geolocation data. And the coordinate data is coming from consumer-grade GPS units mass produced at the lowest possible cost. The antennas are tiny and usually on the back of the device rather than pointed towards the sky. The chipsets are designed to minimize battery usage, because GPS can be extremely battery intensive and generates a lot of heat. They have minimal ability to resolve communication difficulties between your device and GPS satellites, and GPS signals are already relatively weak.

Decisions, decisions. If your budget can’t handle several thousand dollars for a commercial GPS and you only have short term needs you can always look into renting a bluetooth unit. Just make sure to ask if it overrides the onboard GPS chip. You can find GPS rental companies online. There are also consumer-grade Bluetooth GPS units that only cost several hundred dollars. The consumer Bluetooth units aren’t nearly as accurate as commercial units; however, they offer a significant improvement over built-in GPS.

Is Apple’s one-size-fits-all approach starting to fail?

My mother-in-law cracked me up when she asked “What’s the matter with Apple, how come they only make things in one or two sizes?” She’s as non-techie as they come and I think she nailed an important point. I’ve joked about this with friends and colleagues and even mocked about it in presentations. Yet, ever since the Apple September 10th announcement I’ve been wondering: can Apple innovate enough to stay a true technological leader, or are they starting to enter an era of simply copying others and wrapping ‘improvements’ under a luxury brand umbrella? I’m leaning towards to latter. After seeing Tim Cook’s presentation on September 10th, my opinion has started to solidify even more.

Factoid: Everyone will agree, for better or for worse, we are in an era of choice. Look at the variety of Androids. Think about the sheer number of cable and satellite TV channels, the variety of TV shows aimed at a dizzying variety of demographics, music has splintered from the days of major rock bands into hundreds of niche, self published indie groups.  Satellite radio. Most major car manufacturers now have dozens of car models and many of them you can significantly customize. And, even grocery stores now have a ridiculous number of choices for a lot of items that use to only have several manufacturers or producers.

So, what about Apple?

Apple has so far resisted playing to the status quo set by IBM, Microsoft and now Android of allowing endless variations of their products to fit a variety of needs and wants. It wasn’t that long ago, for example, that Dell Computer was a leader in selling desktop and laptop computers. That era has passed and I don’t believe Apple wants to follow in these giants footsteps. Perhaps there is some sort of evolutionary cycle that these leading public tech companies follow, like natural boom and bust cycles that we see in economics, neighborhoods, cities and world economies that Apple won’t be able to escape.

This leads me right back to the September 10th announcement.  Apple seems to have entered an era of incremental improvements in hardware and software: new colors (big whoop), finger print reader (Moto Atrix had that) and faster hardware.  But, the biggest pressure I think they’ll start facing is they are now behind the curve in allowing people to have choices. Real choices…not just new colors for custom cases made of soft silicon rubber. Choices are the way they world is headed right now. Case in point, how long have iPhones had 4-inch screens? How many tens of millions of larger Android screen phones have been sold? Can Apple simply ignore this and stick to their one-size-fits-all guns if the board of directors starts seeing missed opportunities and potentially lower sales?

Android, in comparison to iOS, has more varieties of sizes, manufacturers, shapes and colors than there are grapes for making wine. Buying an Android is like shopping for clothes at any mainstream department store. In addition to a bijillion patterns and colors, you have sizes like XS, SM, M, L, XL, XXL, etc. And then there is relaxed fit, straight fit and athletic fit along with different collar sizes.  This is brilliant from a consumer standpoint, and yes it’s a nightmare for application developers and IT shops that support them. But, developers and IT folks only represent a small fraction of an enormous world-wide porous marketplace full of more consumers, cultures and tastes than perhaps existed in history.

Buying a Mac is like walking into a top-notch art gallery. As you glide along into the next majestic room, shuffling your feet in hushed respect you can hear the mac genius say in an elegant foreign accent, “…and here on this masterfully carved solid white marble pedestal, fabulously embellished with an aluminum case and crystal clear retina view screen, and protected from theft by 12 visible and hidden security features is, ladies and gentlemen…the (audience gasps) Apple Macbook Pro.”

But, at some point even art galleries change up their exhibits as people’s tastes and interests change.  Even galleries have to innovate to stay ahead of the times. Can Apple change? Can Apple adapt to a new era of endless choices? Can Apple reinvent itself?

3 Steps for Determining if Your Website is Mobile Ready

Here are three step for helping determine the mobile ready strengths and weaknesses of your existing website. I’ve had a number of conversations from website teams recently asking the question: “Can we reuse our existing site for mobile users?” I was surprised to learn that the individuals asking me the question had, in fact, never visited their own site on a mobile device.

Note, this blog describes steps that need to be address before you decide whether to build for the web or native applications.

Step One – Create a small focus group of company outsiders, friends as well as employees.

  • Gather as many different types of mobile devices as possible including: iPad, iPhone, Android tablet, and several varieties of Android phones. Try to use a combination of older and newer devices. Don’t fool yourself by simply using all of the latest great versions, especially if your web visitors are the general public.
  • Get a mobile projector, such an Elmo or IPEVO.
  • Write down the common use cases, and the workflows associated with them. An example use case might be logging in to your site. And, a workflow would describe the steps a user takes to complete the login process  from beginning to the end.
  • Visit your website and run through the common use cases.
  • Turn off wireless, if possible, and let everyone experience typical internet speeds to simulate, for example, standing in line at the grocery store.
  • Trade off using different devices.
  • Hire a user interface (UX) designer if you don’t already have one. Bring them on board at the beginning, or as early as possible, in this evaluation process.

Step Two – Create a grading system to help assess the experience everyone had with each device.

  • Were you able to accomplish your task as easily and quickly as if you were at your desk with a full-size laptop or computer?
  • Did you have to do a lot of extra panning and zooming in and out to navigate through the use cases and workflows?
  • Was there any functionality that simply didn’t work, didn’t work correctly, or didn’t work as expected on the mobile device?
  • Were there any aspects of the site that looked different or wrong? For example, was all the text the right size? Was everything in the right place?
  • Were you satisfied with the amount of time it took for pages and images to load?
  • Were you able to comfortably use the site when rotating the phone between landscape and portrait views?
  • Were you okay with how quickly you were able to switch between different pages on the website?
  • Were you able to access secure resources without any problems?
  • And, perhaps most importantly, were there any obvious improvements you would like to see made to make mobile surfing experience better?

Step 3. Apply some commonly known mobile-specific conditions to your findings and see if helps to provide context to everyone’s experience.

  • One-handed plus gestures. It’s a fact that navigating a mobile web is significantly different from a desktop browser. There’s no mouse! Mobile browsing is usually done with one hand, while the other hand is used to hold the device. The screen is driven by what are called gestures. Examples of gestures are when you swipe your thumb upward on a page to scroll it downward, or when you use two fingers, usually the index finger and thumb, to pinch zoom the screen in or out.
  • Smaller Screens. And, of course the screens are much smaller than what you would find on a desktop or laptop. Different devices have different resolutions. And, navigating a full website can seem more cumbersome as you use gestures to navigate around, in comparison to the desktop experience of seeing the entire page, and using your a precision mouse to whip through the different links on a page.
  • Download Speeds. Download speeds on mobile devices vary considerably compared to your work machine hooked up to a reliable local area network (LAN). A site that seems zippy on your work machine, may load much differently on a typical smartphone. Also, for some older phones they may have much less processor power and that may lead to the perception of slower download speeds as the CPU chugs through displaying the page.

How do I interpret the results?

When you are done compile, discuss and analyze the findings with your internal teams and stakeholders.

Good. If most testers successfully navigated the majority of use cases and workflows then you are in good shape, and you may simply need to do some additional tweaking to your site.

Not so good. However, if most testers had unsatisfactory experiences then you’ll need to spend more time looking more closely as what worked and what didn’t work. You may find workflows that are great on a desktop machine that are clumsy and awkward on a mobile device.

Don’t be surprised. Portions of your site may have to be redesigned. You may not be able to include everything that’s in your full site into your mobile site. You may have to spend a lot of time optimizing the site to speed up page load times. Pay special attention to functionality that didn’t work on mobile. Mobile web browsers have well known limitations compared to full browsers. Looking at what didn’t work may help you decide if you need access to native device capabilities.

You’ve just taken a huge first step towards helping your team set the stage for stepping into the mobile world.