首先，和如果你不知道，还有的已经种相似（至少）的Web应用程序。话虽这么说，让我们去回答：

您需要让你CLIENT_ID 的，因为你需要它来调用API（更多信息的这里）。你应该打电话到这个端点（约Instagram的的API端点的此处，你应该阅读：P）：

https://api.instagram.com/v1/tags/SEARCH-TAG/media/recent?client_id=CLIENT-ID&callback=YOUR-CALLBACK

当然，改变搜索-TAG 用户输入，客户端ID 与一个你之前有和您的回调与你的回调函数的名称。

这一号召的响应进来 JSONP ，看起来像这样（从API​​的页面获取）：

  {
    数据： [{
        类型：形象，
        过滤器：晨鸟，
        标签：雪]，
        意见：{
            数据： [{
                created_time：1296703540，
                文：雪，
                从： {
                    用户名：emohatch
                    用户名：戴夫，
                    ID：1242695
                }，
                ID：26589964
            }，
            {
                created_time：1296707889，
                文：#snow
                从： {
                    用户名：emohatch
                    用户名：情绪哈奇，
                    ID：1242695
                }，
                ID：26609649
            }]，
            伯爵：3
        }
        标题： {
            created_time：1296703540，
            文：#Snow
            从： {
                用户名：emohatch
                ID：1242695
            }，
            ID：26589964
        }，
        喜欢：{
            伯爵：1，
            数据： [{
                用户名：mikeyk
                FULL_NAME：迈克·克里格
                ID：4，
                profile_picture：http://distillery.s3.amazonaws.com/profiles/profile_1242695_75sq_1293915800.jpg
            }]
        }，
        链接：http://instagr.am/p/BWl6P/
        用户： {
            用户名：emohatch
            profile_picture：http://distillery.s3.amazonaws.com/profiles/profile_1242695_75sq_1293915800.jpg，
            ID：1242695，
            FULL_NAME：戴夫
        }，
        created_time：1296703536，
        形象：{
            low_resolution：{
                URL：http://distillery.s3.amazonaws.com/media/2011/02/02/f9443f3443484c40b4792fa7c76214d5_6.jpg
                宽：306，
                高度：306
            }，
            缩略图：{
                URL：http://distillery.s3.amazonaws.com/media/2011/02/02/f9443f3443484c40b4792fa7c76214d5_5.jpg
                宽：150，
                高度：150
            }，
            standard_resolution：{
                URL：http://distillery.s3.amazonaws.com/media/2011/02/02/f9443f3443484c40b4792fa7c76214d5_7.jpg
                宽：612，
                高度：612
            }
        }，
        ID：22699663，
        位置：空
    }，
    ...
    ]
}
 

然后你只需要处理这种反应，做任何你想做的事情：）

I would like to build a small 'instant image search' app powered by Instagram photos. This would be like Google Instant where you start typing and results are displayed/updated as you type more letters.

You can see a live demo app powered by Google Images instead. I know this is possible with larger engines (Google, Yahoo!, Bing) but I have no idea if Instagram will allow this. Can anybody familiar with the API offer help on this?

If it's not possible to search via the API that makes sense. I just wanted to check here first since there are so many knowledgeable programmers.

First of all, and in case you didn't knew, there's already one similar (at least) web app. That being said, let's go to the answer:

You need to get your client_id, since you need it to call the API (More info here). You should be making calls to this endpoint (More info about Instagram's API endpoints here, you should read this :P):

https://api.instagram.com/v1/tags/SEARCH-TAG/media/recent?client_id=CLIENT-ID&callback=YOUR-CALLBACK

Of course, change the SEARCH-TAG with user input, CLIENT-ID with the one you got before and YOUR-CALLBACK with your callback function's name.

The response to this call comes in JSONP and looks like this (Taken from the API's page):

{
    "data": [{
        "type": "image",
        "filter": "Earlybird",
        "tags": ["snow"],
        "comments": {
            "data": [{
                "created_time": "1296703540",
                "text": "Snow",
                "from": {
                    "username": "emohatch",
                    "username": "Dave",
                    "id": "1242695"
                },
                "id": "26589964"
            },
            {
                "created_time": "1296707889",
                "text": "#snow",
                "from": {
                    "username": "emohatch",
                    "username": "Emo Hatch",
                    "id": "1242695"
                },
                "id": "26609649"
            }],
            "count": 3
        }
        "caption": {
            "created_time": "1296703540",
            "text": "#Snow",
            "from": {
                "username": "emohatch",
                "id": "1242695"
            },
            "id": "26589964"
        },
        "likes": {
            "count": 1,
            "data": [{
                "username": "mikeyk",
                "full_name": "Mike Krieger",
                "id": "4",
                "profile_picture": "http://distillery.s3.amazonaws.com/profiles/profile_1242695_75sq_1293915800.jpg"
            }]
        },        
        "link": "http://instagr.am/p/BWl6P/",
        "user": {
            "username": "emohatch",
            "profile_picture": "http://distillery.s3.amazonaws.com/profiles/profile_1242695_75sq_1293915800.jpg",
            "id": "1242695",
            "full_name": "Dave"
        },
        "created_time": "1296703536",
        "images": {
            "low_resolution": {
                "url": "http://distillery.s3.amazonaws.com/media/2011/02/02/f9443f3443484c40b4792fa7c76214d5_6.jpg",
                "width": 306,
                "height": 306
            },
            "thumbnail": {
                "url": "http://distillery.s3.amazonaws.com/media/2011/02/02/f9443f3443484c40b4792fa7c76214d5_5.jpg",
                "width": 150,
                "height": 150
            },
            "standard_resolution": {
                "url": "http://distillery.s3.amazonaws.com/media/2011/02/02/f9443f3443484c40b4792fa7c76214d5_7.jpg",
                "width": 612,
                "height": 612
            }
        },
        "id": "22699663",
        "location": null
    },
    ...
    ]
}

Then you just need to process this response and do whatever you want with it :)