iPhone Gems: Doodle Bomb, Isaac Newton’s Gravity + Tumbledrop

“Physics engines”—essentially, tools that enable game developers to animate on-screen objects with realistic motion, gravity, and momentum—have made video games a lot more interesting and believable over the years, sometimes even creating fun by just setting up domino-style events to be watched somewhat passively. Early iPhone games including Touch Physics and Aqua Forest demonstrated the fun and power of good physics engines, and this week, we’re looking at three recent puzzle games that similarly use physics as their foundations and inspirations: Doodle Bomb, Isaac Newton’s Gravity, and Tumbledrop. They’re each unique, and once again, the ones with the most famous or interesting names aren’t necessarily the best.

iPhone Gems: Doodle Bomb, Isaac Newton’s Gravity + Tumbledrop 2

Our top pick of the bunch is Tumbledrop. Read on for all the details.

Doodle Bomb


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Indie developers for the iPhone and iPod touch have taken a wide range of approaches to creating games: some have tried to emulate or improve upon the aesthetic styles of larger competitors, others have focused little on graphics and sounds, and still others have fallen back on deliberately simplistic visuals and sounds as a sort of “whatever, the game’s $2” response to those who might hope for more. Doodle Bomb – Physics Puzzle with a Bang ($2) from Bottle Rocket is in the latter category, featuring simple, hand-drawn art on what looks like grid paper backgrounds, and only the most basic sound effects. It has one cute touch: a main character who peeks out from a pipe, tossing bombs into single-screen mazes in order to trigger switches that collectively open an escape door.


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Control, and thus the game, are extremely simple: you point at a place on the screen, and the distance and angle you’ve picked relative to the guy in the pipe determines where and how fast his bomb will fly. Sometimes, the key is to launch a bomb into a pipe; other times, it’s to time one bomb to trigger a switch while another is in the cogs of a moving gear, or to bounce a bomb between two mouse-shaped springboards while you wait for its fuse to burn down. Tilting the iPhone or iPod touch modestly influences the movement of the bomb, but most of the action involves proper aiming and timing. You’re trying to use as few bombs as possible to open the escape door, but you can move along even if you don’t match or beat the par number—a fact that lets you breeze through the 50 missions rather than getting frustrated and stuck, for better or worse.


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To the extent that Doodle Bomb’s puzzles are legitimately fun and occasionally pretty smart, the game earns its $2 asking price without a problem, but there’s little doubt that the game’s first half is easy to rush through, and that the aesthetics aren’t anywhere as impressive as they need to be: there’s no music, and deliberately sketchy or not, the artwork doesn’t make a fantastic impression. This is a very good start, but it’s easy to imagine a more engaging and polished sequel making more of the fun concept. iLounge Rating: B.

Isaac Newton’s Gravity


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Though a good physics engine can become the foundation of a great game, developers can also get stuck in the trap of assuming that physics alone can make a title worthwhile. That’s what happened with Namco’s Isaac Newton’s Gravity ($4), a puzzler that offers its own 50 levels at twice Doodle Bomb’s price, and despite significantly more effort in the art and audio departments completely misses out in the “fun” category. Here, you’re presented with a screen that has an obvious hole for a ball to fall from, and a switch at the end of a maze that needs to get pressed. Your goal is to somehow get the ball or another object to hit the switch, in many cases countering the effects of gravity using a combination of puzzle pieces and momentum. Later stages swap the ball with a car, and vice-versa, presenting you with more and different puzzle pieces to use.


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From a technical standpoint, Isaac Newton’s Gravity has a lot going for it. There’s a simple but pleasant soundtrack, the flat backdrops are individually beautiful, painting-quality pieces of abstract artwork, and there are little specular lights that make some of the puzzle pieces glimmer more interestingly than they otherwise might look as flat objects. Though special effects are used far too sparingly here to make this game shine as it could and should, it’s obvious at the very least that aesthetics weren’t totally being ignored. That said, the occasional appearances of Isaac Newton as a cartoony tipster feel as if they were tacked on, and should have been made more visually appealing.


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Unfortunately, Isaac Newton’s Gravity is pretty close to patently un-fun. It charmlessly starts levels by presenting you with the flat, boring maze that you’re going to need to move the ball or car through, and gives you a series of buttons that you’re supposed to push to see what happens if you add nothing to the maze, and then try and re-try every time you add or reposition another item. There’s a lot of fiddling to do here: press a button to call up a list of pieces, pick a piece to add to the maze, move the piece around, then go back to the list of pieces and do it again. The pieces you’re given are boring, need to be rotated via an initially counterintuitive control mechanism, and sometimes accidentally get moved when you’re trying to turn them. A hint system lets you “buy” tips on how to solve the puzzles, which we found ourselves using again and again because the solutions were so uninteresting. If it wasn’t for the level editor, which enables you to design and share your own stages—sadly, only with Bluetooth-connected friends—we’d find it very difficult to see this game as nearly worthy of a $4 asking price; even so, it’s not one we’d recommend with gusto at this point in time. More objects, better maps, and additional polish might save it from obscurity. iLounge Rating: C.



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The best of today’s physics puzzlers is Tumbledrop ($2) from Starfruit Games, which manages to properly balance fun, aesthetics, and challenge in a right-priced package. Here, you get 60 different physics-based levels, with more promised in a free update, and unlike Isaac Newton’s Gravity, there’s no screwing around: every tap does something, and your goal on each stage is to tap as few times as possible, moving a cartoony star from a high, precarious position to stable safety on a platform at the bottom of the screen. Each tap removes one piece of the structure under the star, and if you choose the wrong pieces—or don’t react quickly enough after seeing a collapse in motion—the star will tumble into the water next to the platform instead of surviving. Every stage can be completed in four or fewer moves; you get bonus points for completing a stage with three or fewer taps, and occasionally get the thrill of winning after only one tap.


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What makes Tumbledrop work, more than anything else, is its graphical style: white-outlined objects are set against stylized cloudy backdrops with deliberately chunky animated water, none of which is amazing in isolation, but they all integrate perfectly together with the music box-like soundtrack to create a relaxing, cartoony experience. The excitement is partially in the gentle physics on display when you tap to remove a piece, causing shifts in the rest of the puzzle, and then the reward of an animated rainbow and confetti shower that awaits when you complete the level, adding to the tiny smiling faces of the remaining puzzle pieces.


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If there’s any major issue in Tumbledrop, it’s the same one we saw in Doodle Bomb: you can move on even if you exceed the number of moves, which makes it very easy to progress through the game; consequently, it quickly becomes obvious that there are relatively few variations in the types of blocks, and similarly few changes in the backgrounds or audio. While this is a very good title in its current form—better than either of the others above—more diversity would certainly help it to become truly great; it has the type of gameplay, style, and fundamentally strong physics to become a true iPhone and iPod touch classic. iLounge Rating: B+.

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