Find Your Tweeting Neighbor on iPhone with GeoLocation

iPhone OS 3.0 is now available, and developers can take advantage of the newly introduced geolocation feature in Safari browser.

To try it out quickly, I used Twitter Search API again to create a tiny test app called, NeighborTweet, which enable you to find out who are tweeting in your neighborhood. Basically, what it does is that obtain your location, and pass the latitude and longitude data to Twitter search and display the result tweets.

Try it out on your iPhone with:
Short URL http://bit.ly/K0ZaE
or
This QR Code with scanning app like BeeTagg.

If you are interested in learning more on Twitter search API and geocode, please read Twitter Wiki.

OK, now here’s the code.
To find out your location with Geolocation class is simple – you just call getCurrentPosition() method. This initiates an asynchronous request to detect the user’s position.

navigator.geolocation.getCurrentPosition(someFunction)

Get latitude and longitude, by using coords instance:

latitude = position.coords.latitude;
longitude = position.coords.longitude;

Here’s an actual code I used to create the sample app:

if (navigator.geolocation) {
  navigator.geolocation.getCurrentPosition(function(position) {
    callback(position.coords.latitude, position.coords.longitude);
  });
} else {
  alert("Geolocation services are not supported by your browser.");
} 

function callback(lat,lon){
  // twitter search json-p callback
  var geocode = "&geocode=" + lat + "%2C" + lon + "%2C1mi";
  var fullUrl = url + geocode;
  ...
}
var url = "http://search.twitter.com/search.json?callback=getTweets";

function getTweets (json) {
  // display json data
  ...
}

References

Geolocation References:

• Safari Reference Library – Getting Geographic Locations – Apple Developer Connection
• Using geolocation – Mozilla Developer Center
• Geolocation API Specification – W3C Working Draft

More References:

• Twitter Search API Wiki
• Remote JSON – JSONP

TweetTrendDunno – Played with APIs

I had a plenty of time to stay home and play with code right now so I mashed Twitter trend API, mixed with some BOSS news and image search stuff I used before, also Microsoft’s new Bing search results to create some silly and handy web app called TweetTrendDunno.

Basically, this grabs Twitter “trending topic” terms, and as a user click on each term you want to know about, it displays news articles, images, and Bing results (usually summary from Wikipedia helps you to figure out what the term means in general).

If you are Twitter user and ever wonder what people are talking about, give TweetTrendDunno a try!

Mobile Safari for iPhone 3 includes Geolocation

Although W3C’s document, The Geolocation API Specification is still in draft state and not yet finalized, major browsers are working to support this functionality and as we all expected, Mobile Safari is not an exception.

According to ComputerWorld blog, the geolocation API has been implemented for the upcoming API. Apparently, Seth of ComputerWorld tried the test webpage, built by Doug Turner for Mozilla on a 3.0B5 iPhone’s Mobile Safari.
This screenshot is grabbed from the CompWorld’s blog.

Obviously I don’t have access to the new iPhone so I just tested the test page (http://people.mozilla.org/~dougt/geo.html) using Geolocation API watchPosition() method, on Mozilla 3.5. (And this should works similarly on Fennec too. I wish I could try on an actual device!)

I am using my old PowerBook G4, with Comcast,. Since this Mac is not equipped with GPS device, Firefox gathers information about nearby wireless access points and computer’s IP address.

Nice! I can’t wait to see this working on iPhone!
Especially, NextMuni.com with location enabled, that tells me where I am and where the nearest bus stop!