It’s no secret that Boston is a hotspot for mobile. Here are four new iPhone, Android and Blackberry apps that were built, powered by, or recently released here in the Hub.

Boston Herald Baseball 2011

Aimed at Red Sox fans with Opening Day just last week, The Boston Herald has more formally introduced their first ever paid app . The app is available on Android, iOS and Blackberry devices, and The Herald told us that Windows Phone 7 is on the way soon, too.

Tom Rose, Senior Editor at The Herald shared with us, “Newspaper publishers have not launched many paid apps for sports coverage. … We decided we wanted to deliver a complete package for Red Sox fans, without resorting to in-app links to other sites. While paid sports apps from the Miami Herald, St. Louis Post-Dispatch and Philadelphia newspapers send their readers to Stats Inc., CBS Sports and ESPN mobile sites for stats, we have integrated our own stats package into the app.”

The app will cost you $1.99, and includes in-app advertisements at the bottom of the page as well. But with the price comes a very clean interface with scores, standings, schedules, twitter feeds, and of course Herald news, editorial content about the Boston Red Sox and the MLB. On the citizen journalism front, there is even a unique “You Report” section of the app where you an submit videos, photos, and even your own story to The Herald. The app also seems to be leveraging Disqus, a commenting system used by many blogs, to provide “Sox Chat” on topics like your favorite Sox player and predictions for the season.

Magellan Jets O.W.L. Search

Private jets and iPhone apps? Absolutely. Braintree based Magellan Jets provides Boston’s rich and famous with private jet memberships and charter flights. Named after Ferdinand Magellan’s passion for discovery, this company is continuing its commitment service (which includes in flight wi-fi) by introducing its own iPhone app.

Called O.W.L. Search for ‘One Way Leg Search,’ the app allows users to search a live, updated list of available private jet flights with Magellan. Empty legs become available when the company’s jets reposition from one airport to another. The app also allows users to see search more traditionally for flights as well as by leveraging the phone’s GPS to automatically identify airports closest to you.

The company describes the app as a natural step from their already successful Empty Leg Link tool on their website, which provides similar support. “O.W.L. Search is a revolutionary tool,” shared Joshua Hebert, CEO of Magellan Jets. “It will provide the instant gratification my clients have been yearning for, which is an incredible thing.”

NCAA March Madness On Demand

Okay, so this is perhaps not an app built in Boston, but certainly one powered by a Boston company. Akamai recently announced that its HD Network was the exclusive video delivery platform for all of the live streamed, on demand video in the 2011 NCAA Division I Men Basketball Tournament. March Madness On Demand (MMOD) delivered all 67 NCAA tournament games online and to your iPad, iPhone and Android devices over the NCAA’s dedicated apps.

This means Akamai delivered live games to more than 1.9 million people every day online and to 680,000 people on their smartphones and tablets. According to Akamai, compared to last year, by the event’s end the NCAA enjoyed a 63% increase in total visits across the 2011 NCAA March Madness On Demand broadband and mobile apps and a 17% increase in online video consumption.

Boston Public Garden Tour

Historic places and mobile are two things Boston is known for. Announced earlier this month and expected to hit app stores soon, smartphone users visiting the Boston Public Garden will be able to enjoy sculptures like Make Way for Ducklings in a new way. The Friends of the Public Gardens non profit is releasing a virtual tour app for iPhone, Android and Blackberry users. The app was built by Boston-based mobile app generator TourSphere, which specializes in rolling out apps for museums and historic sites and parks.

The Public Garden’s original digital tour was released in 2009 as an .mp3, and its Founder and President Henry Lee (who’s voice is recorded for the tour) shared, “This application will bring the Friends of the Public Garden to the interactive digital age in a groundbreaking way that will give park lovers a whole new experience. We are pleased to give visitors to the Garden an easier way to connect with the stories behind this magnificent place, and with the work of the Friends.”

The organization says the interactive tour includes an original soundtrack, background information, along with options to experience the tour in different ways – from a longer, 45 minute tour to on a site-by-site basis. Several site tours feature guest narrators like Senator Ted Kennedy. The Friends of the Public Garden says the apps will be released on Presidents Day, April 19th, for free.