WapReview

The mobile version of Google search mirrors the simple design of Google's desktop site.

By default searches return combined results from Google's mobile, local, web and image indexes. A mobile phone icon is displayed next to results links pointing to mobile friendly sites. Google identifies mobile sites by a number of clues including the presence of link rel="alternate" media="handheld" headers.

On non-smartphones, once you have performed an initial search, there's a drop down at the bottom of each result page that let you limit searches to Images, Places, News, Blogs or Mobile. 

Pages from full-web sites are transcoded on basic devices. On some devices it's  possible to disable the transcoder in Google Search's Preferences menu. 

Socialize your search. AskFriends is a wrapper for Google search lets you share your search query with your friends on Facebook. The mashup posts your query on Facebook's wall and redirects you to Google's search engine results page. Who will help you the most?

The mobile web version of Yahoo Search (powered by Bing).  Yahoo uses browser detection to deliver several different versions of the search results page, optimized to the browser's capabilities. On some low end devices, search results link to transcoded desktop sites. The quality of the transcoding leaves a lot to be desired and it doesn't seem to be possible to disable it.

A new search engine that searchs for:
Local busineses, Sports scores, Lowest price, Today's horoscope, WiFi Hotspots, Movie showtimes, Flights, Weather forecasts and Stock Quotes. It will also give you driving directions to any search result that has a physical location. The search syntax is similar to Google i.e., "94103 Camera", "oakland a's". See the "search tips" link on the site for the exact syntax. Navigation is pretty inituitive except on older Openwave browsers where you have to scroll all the way to the bottom of the page before the "Search" or "Directions" softkey appears.

Microsoft unveiled a new search engine Bing, in June of 2009 with considerable fanfare.  Search relevance is good and a new related search feature works well. Local searches like " Sushi near 94102" return click to call numbers, photos and maps.  It's one of the best ways to find nearby shops and attractions with your phone. There are separate news and image searches.

Unfortunately, Bing seems to be almost completely unaware of the existence of mobile optimized web sites. Mobile sites are getting indexed and do occasionally occur in the results, usually buried a page or two down. But they aren't consistently flagged as mobile

In contrast Google's mobile searches are much more mobile aware with the option to filter results to mobile web only on basic devices.

AOL Mobile Search (powered by Google). Separate web and local searches.

Ask.com's mobile search uses Ask's own search engine. I'm not impressed by the quality of Ask's results which tend to favor content farms and splogs over original and relevant content

Besides web search, Ask's mobile search offers, Image, news and shopping search

A mobile optimized "social" search engine that claims to give more relevant results by tapping into the "collective wisdom of your social world".  Search results for queries I tried seemed to come from Bing and Twitter search. If you don't like ExploreWWW's results the site has buttons that let you retry your query on Google, Bing or Yahoo.

Real time Twitter search. Most of the top tech bloggers (Scoble, Steve Rubel, Jason Calacanis) are active on the Twitter micro blogging platform. If you want to keep up the latest web 2.0 trends you really need to use Twitter. Twitter Search offers an alternative to following hundreds of people on Twitter, which can be pretty time-consuming. With Twitter Search you can do a keyword search against all public Twitters for the topics and memes that interest you.

Twitter Search isn't really a mobile site but its small page size and minimal use of images let its basic search functions work even on the limited built in browsers of most phones. Twitter Search's advanced search options which let you filter by user, tag, attitude or language require Javascript and don't work on most phones although Opera Mini handles the advanced search with no problems.

Mobile image, video and game search site.

Yippy (formerly Clusty) used to be a meta search engine that submited your query to multiple search engines like Google, MS Live, Yahoo, etc. and returns the top hits from all the engines. The current site appears to use a sigle unidentified search provider. Web results are pretty good. Yippy says it does not to track users.

Below the web results there are a large number of links to a paid research site.

Sensis is one of the many brands belonging to Australian fixed and mobile telecommunications and Internet giant Telstra (Wikipedia). The Sensis brand is used for Yellow and White pages directories both online and mobile and for an online web search engine, "The search engine for Australians". Sensis search's default behavior is to return sites, products and services of interest to Australians. This is a subtle distinction from the Australian versions of Google and Yahoo which return global results by default with Australian only results being an option.

Sensis Search is "Powered by Yahoo" so the results come from Bing as Yahoo itself is now Bing powered.

WML based search site and mobile site directory. Allows you to filter on site language so that it only returns english sites (or most european including Scandinavian languages or chinese).

WML-only site directory and search engine. Search results seem somewhat limited.

Old school WML directory and search engine. Search seems to be broken and the directory has lots of dead links.

Gune is a meta-search engine in English from Brazilian development house,  Handcase.  Search uses Google and Bing for results, and returns the 10 ten results from each search engine.

27-Jan-2013: Currently broken, all tested queries return no results.