Top iPhone apps: "Flappy Bird," messaging apps

"Flappy Bird" crosses a "Super Mario World" aesthetic with the "Tiny Wings" tapping and flapping, while Kakao and WhatsApp enjoy a surge in popularity in Korea and Brazil respectively. Details of these and other top free iPad applications by country for the week, by number of downloads, recorded on January 24, can be found below.

Flappy Bird (Games)
There's more than something recognizable about this -- the "Super Mario World" pipes, the "Tiny Wings" approach to flight -- it sounds simple but is actually really challenging.

Dragon Quest Monsters: Super Light (Games)
The first free iPhone app in the "Dragon Quest Monsters" series: recruit party members, find and collect monsters, make Nintendo re-think its policy of not releasing a full Pokémon game on smartphones.

Motocross Meltdown (Games)
Motocross stunts, bike customization and online competition feature, as do in-app purchases of which the $4.99 pack of in-game currency is most popular.

Kia Game On (Games)
Tennis pro Sam Groth supplies six different super-powered serves for you to return, turning your phone into a tennis racket handle for you to do so in response to TV, online and outdoor ads.

Mahjong Fun (Games)
China's traditional tile-based game polished to a shine and powered by net firm Tencent, with the most popular in-app purchases amounting to $0.99.

Quizduell (Games)
German-language head-to-head quiz game for two players with 6 rounds' worth of 3 questions each; app maker FEO adds 500 new questions every day and accepts new ones from its players. The $2.99 premium upgrade provides avatar customization and color scheme options.

94 Degrees (Games)
General knowledge meets childhood game as players tap an image -- whether it be a map, a face, an animal or body -- at the point that they think best answers the question. Are you hot? Cold? Getting warmer? $1.99 unlocks the premium app.

South Korea
KakaoTalk Messenger (Social Networking)
Group voice calls, chat rooms and chat room appointments, emoticons, stickers and themes. Cosmetic packs tend to come in at $1.99.

Flappy Bird (Games)

Carmageddon (Games)
Classic and then-controversial 1990s video game "Carmageddon" arrived a few months ahead of the first "Grand Theft Auto" and approached players with a similar philosophy, allowing them to express themselves conventionally or with a more anarchic sensibility. Part of the App of the Day promo.

WhatsApp Messenger (games)
Uses data connections (3G or WFi) instead of text message allowances to send and receive messages, images, audio and video. Free for the first year, $0.99 per annum thereafter.