苹果的iPad Mini在很多方面都是iPad 2的小复制品。在JavaScript中,是窗口。navigator对象为Mini和iPad 2暴露相同的值。到目前为止,我为检测差异而进行的测试还没有成功。

为什么这很重要?

由于iPad Mini和iPad 2的屏幕像素相同,但实际尺寸(英寸/厘米)不同,它们的PPI(每英寸像素)也不同。

为了提供友好的用户界面,web应用程序和游戏会根据用户的拇指或手指位置调整某些元素的大小,因此,我们可能想要缩放某些图像或按钮以提供更好的用户体验。

到目前为止我尝试过的事情(包括一些非常明显的方法):

window.devicepixelratio CSS元素宽度,单位为cm CSS媒体查询(如分辨率和-webkit-device-pixel-ratio) SVG图形在类似的单位 在设定的时间内进行各种CSS webkit转换,并使用requestAnimFrame计算呈现的帧数(我希望检测到可测量的差异)

我没办法了。你呢?

更新 谢谢你的回复。我想对那些投票反对检测iPad mini和iPad 2的人发表评论,因为苹果有一个规则。好吧,这是我的理由,为什么我觉得知道一个人用的是iPad mini还是iPad 2真的很有意义。随你怎么解释我的推理。

The iPad mini is not only a much smaller device (9.7 inch versus 7.9 inch), but its form factor allows for a different usage. The iPad 2 is usually held with two hands when gaming unless you're Chuck Norris. The mini is smaller, but it is also much lighter and allows for gameplay where you hold it in one hand and use another to swipe or tap or whatnot. As a game designer and developer myself, I'd just like to know if it's a mini so I can choose to provide the player with a different controlscheme if I want (for instance after A/B testing with a group of players).

为什么?事实证明,大多数用户倾向于使用默认设置,所以当玩家第一次加载游戏时,不要使用虚拟拇指杆,而是在屏幕上放置一些基于点击的控制,这是我和其他游戏设计师希望能够做到的。

所以恕我说,这超出了粗手指/指导方针的讨论,这是苹果和所有其他供应商应该做的事情:允许我们唯一地识别你的设备,以不同的方式思考,而不是遵循指导方针。


当前回答

那么微基准测试呢,在iPad 2上计算大约需要X微秒,在iPad mini上计算大约需要Y秒。

这可能不够准确,但iPad mini的芯片可能在某些指令上更有效率。

其他回答

在iOS7中,用户可以调整一个系统范围的设置:当内容太小而无法阅读时,可以更改文本大小设置。

文本大小可以用来形成合理尺寸的UI,例如按钮(在iPad Mini Retina上测试,以响应文本大小设置的变化):

padding: 0.5em 1em 0.5em 1em;
font: -apple-system-body;    

(示例按钮CSS,感谢jsfiddle和cssbuttongenerator)

这是一个疯狂的镜头,但iPad 2和iPad mini的区别之一是前者没有三轴陀螺仪。也许可以使用WebKit设备定向API来查看您可以从中获得什么样的信息。

例如,该页似乎建议您只有在设备具有陀螺仪时才能获得rotationRate值。

对不起,我不能给一个工作POC -我没有访问iPad mini。也许对这些定向api有更多了解的人可以在这里插话。

播放一个立体声音频文件,比较右声道和左声道音量大时加速计的响应——iPad2有单声道扬声器,而iPad Mini有内置立体声扬声器。

需要你的帮助来收集数据,请访问这个页面,帮助我收集这个疯狂的想法的数据。我没有iPad mini,所以我真的需要你的帮助

不要补偿iPad mini和iPad 2之间的差异,除非你也补偿了胖手指和瘦手指之间的差异。

Apple appears to be deliberately trying not to let you tell the difference. Apple appears not to want us to write different code for the different size versions of iPads. Not being part of Apple myself, I don't know this for sure, I'm just saying that this is what it appears like. Maybe, if the developer community comes up with a fancy detector for iPad minis, Apple may deliberately break that detector in future versions of iOS. Apple wants you to set your minimum target size to 44 iOS points, and iOS will display that in two sizes, the larger iPad size and the smaller iPhone/iPad mini size. 44 points is plenty generous, and your users will certainly know if they are on the smaller iPad, so can compensate on their own.

I suggest stepping back to your stated reason for asking for the detector: adjusting target size for end user comfort. By deciding to design for one size on the large iPad and another size on the small iPad you are deciding that all people have the same size fingers. If your design is tight enough that the difference in size from an iPad 2 and an iPad mini makes a difference, than the size of fingers between me and my wife will make a bigger difference. So compensate for user finger size, not iPad model.

I have a suggestion on how to measure finger size. I'm a native iOS developer, so I don't know if this can be accomplished in HTML5, but here's how I would measure finger size in a native app. I'd have the user pinch two objects together, then measure how close they get together. Smaller fingers will get the objects closer together, and you can use this measurement to derive a scaling factor. This automatically adjusts for iPad size. The same person will have a larger measurement of on screen points on an iPad mini than on an iPad 2. For a game you can call this a calibration step, or not even call it out. Have it as a starting step. For example in a shooting game have the player put the ammo in the gun with a pinching motion.

iPad 2和iPad Mini的电池大小不同。

If iOS 6 supports it, you can get the current battery level from 0.0..1.0 using window.navigator.webkitBattery.level. At some level either in hardware or software, that is likely calculated as CurrentLevel / TotalLevel, where both are ints. If so, that will result in a float which is a multiple of 1 / TotalLevel. If you take lots of battery level readings from both devices, and calculate battery.level * n you might be able to find a value of n where all the results start to be close to integers, which will give you iPad2TotalLevel and iPadMiniTotalLevel.

如果这两个数字不同,并且相互素数,那么在生产中您可以计算电池。* iPad2TotalLevel和电池。level * iPadMiniTotalLevel。更接近整数的值将指示正在使用的设备。

对不起,这个答案中有太多的如果!希望会有更好的事情发生。