Monday, December 7, 2009

An App for Touch Travelers

Mark Sigal wrote a post titled "Touch Traveler: London, Paris and only an iPod Touch" for the O'Reilly Radar blog in August 2009, right before we started development on our first iPhone app.

This article detailed his trip though Europe using only an iPod Touch for maps, to plan itineraries, and to find restaurants and tourist attractions. For the most part, it seems this was a success, but there were a few hiccups:
In London, this meant that 99% of the time, I had decent Wi-Fi connectivity at my hotel but no connectivity when mobile. This was key as we walked a ton, and took the Underground a lot (it is a great service).

Not having reliable connectivity in mobile contexts crippled some of the utility of Google Mobile Maps since it essentially removed the Real-Time goodness of the app. Moreover, it crimped the ability to search for nearby restaurants when on the move.

Inspired by this (and by horror stories from friends of how much they'd paid for data roaming while traveling), we tried to come as close as possible to the perfect iPod Touch travel guide to Prague. It's important to note that sales of the iPod Touch are nearly equal to sales of the iPhone, meaning an app that can work on both devices can reach double the audience of an app that requires a full-time internet connection.


First off, the revelation (for me) was how much the Google Mobile Maps App on iPod Touch completely changes the equation when traveling. Touch-based control with a virtual keyboard is the perfect UI for zooming in and out of geo-locales, and Mobile Maps offers a workflow whose predictability and logical structure both de-mystifies and anchors foreign travel.

While we can't offer all the functionality of Google Maps in our app (e.g. a database large enough to handle driving/walking directions would make the app unacceptably large and complex), we can offer something that Google Maps can't - the ability to work offline, without an internet connection. So using an iPod Touch without 3G, or an iPhone but don't want to pay data roaming charges to use Google Maps online, you can still use the Nelso Prague app for maps, with a pinch-and-push interface like that found in the online version.


What was almost magical was how Maps seemed designed to watch proactively in the background for a live connection so it could autonomously update location data when connectivity was intermittent.

Actually, it wasn't Google Maps updating the location data for his iPod Touch when it sensed a WiFi connection, it was the CoreLocation API in the iPhone OS, which makes this location data available to every app (for example, when using the "Nearby" tab in our app).

But we can do better than hoping that the user passes by an open WiFi spot to get a location (obviously, someone using our app with an iPhone 3G or 3GS has access to GPS). Our coverage of Prague is so dense that we can do pseudo-location sensing simply by asking the user to enter the name of a business or landmark near them. This would not work with most offline guides that contain fewer than 1000 locations in a city, but with more than 10,000 locations in the center of Prague, there is a very good chance that we have GPS coordinates for the bar or restaurant you are sitting in while doing a search. If you enter that name in the search box for "Near", we can give the user distance-sorted search results as good as, and usually better than, those possible with GPS (e.g. if you are in a small cafe, the margin of error for your location will be only a few meters, much better than the average error of the GPS in an iPhone).

Searching for Restaurants, Tourist Attractions, etc.

With over 10,000 businesses and tourist attractions in more than 200 categories, we've got this covered.


The ability to visually follow block-by-block, and see the storefront of a business blocks or miles away was very powerful.
We've included over 5,000 photos in the Nelso Prague iPhone app, so you can see the front (and sometimes the interior) of most businesses in Prague. Even with connectivity, Street View is not necessarily a good source of storefront images, as you can see in the view of Pařížská embedded below (in this case, trees planted between the street and sidewalk make it difficult to read many of the store names).

What's Missing?

Although we feel we have a strong 1.0 release, there are of course many things missing from the Nelso Prague iPhone app. Because we started with our local search database (rather than a travel guide database), we need to add a lot more content for tourists to the app (e.g. how to get in from the airport, top restaurant picks, how to use the subway, etc.). Speaking of the subway, we'd like to add at the very least a public transport map to the app, and even better would be routing information for the subways, buses, and trams (we did include public transport info for businesses in this version, but we can't help you find your way to that subway/bus/tram stop).

We're always open to suggestions/comments on our app. You can send us email at or leave a comment below.

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Anonymous said...

I'm coming to Prague for Silvester. I'm looking forward to see what your iPhone App can offer.

Jack DeNeut said...

@Anonymous We're always looking for feedback about the app. Feel free to comment on this post, or even better, write a review on the App Store.