Study: make it fast
Studyblue is dedicated to facilitate the learning with mobile devices. It supports iPhone, iPad learning. It can help to generate the test and quiz based on the notes you took. It is also very quick to take the flash card.
We may need more!
You maybe definitely surprised for how successful of the Dan Provost Kickstarter project: iPhone4 Tripod Mount & Stand.
Until present, they have raised $102,362, with 4017 backers. Can you imagine this number? I and my friends had talked about the similar idea in the last year, when we drove our car and wanted to use the GPS function of iPhone. With a simple stand, you can do many more jobs easily!
It is Dan and his friends who are doing a good job to turn the simple idea to a real product. Most important, they utilized kickstarter as the platform to raise the initial funding. Thomas Gerhardt and Dan Provost also founded a company called theglif to manufacture this.
If you are interested in their past design, please go to therussiansusedapencil. You may be impressed for their taste of a product design.
Bottom line? iPhone4 definitly needs a sharp stand: cute, easy to carry on, simply love it!
Fast, Reliable, and Scale
Probably, many people know Cassandra, HBase, CouchDB, and MongoDB. But, It is not that popular for people to know Riak, a relatively new NonSQL database.
1. Expected minimum users: 1 million. Design to accommodate 10 million by the end of the year and have a plan for scaling out to tens of millions. (This is the 1x 10x 100x rule of estimation of which I am a fan)
2. Expected amount of data stored per experiment: 1.2 TB
3. Expected peak traffic: approximately 75 GB per hour for two 8 hour periods following the conclusion of an experiment window. This two day period will result in collection of approximately 90% of the total data.
Remain highly available under load
4. Provide necessary validation and security constraints to prevent bad data from polluting the experiment or damaging the application
5. Provide a flexible and easy-to-use way for data analysts to explore the data. While all of these guys are great with statistics and thinking about data, not all of them have a programming background, so higher-level APIs are a plus.
6. Do it fast.
After comparing HBase, Cassandra, and Riak very carefully, they chose RIAK. That’s the simple answer. There is also another open source app called LUWAK dedicated for reading/writing large size of blocks to RIAK.
StorageJS for mobile device, for local storage
With the following command, you can finish your storage task:
var value = storage.get(key);
There is also a benchmark test of the file size using different methods including behaviour, cookies, Google Gears, Localstorage, and Widget.
You can preview it here.
As matter of fact, we have written several other cool demo of Game, sound effect, for example the sound manager, which also can help you get started for Web based video game.
Graph Database: for Social Network
We have written an article months ago dedicated to describing the power of graph based database: Open source graph database – Neo4j and Infogrid.
Today, we will introduce another graph database, FlockDB. It is described as distributed and fault tolerant database. It is made by Robey Pointer, Nick Kalle, John Kalucki, Ed Ceaser, employees of Twitter.
Very interestingly, different from most Graph database which are mostly written with C or C++, Flockdb is written by Scala, a very new language. As matter of fact, Twitter is said switching their entire products to Scala. Scala has excellent performance for distributed systems, easy to scale. Compared with Ruby, it has more advantages of memory garbage collection.
How good of FlockDB?
Based on the dev team description:
1. Twitter uses FlockDB to store social graphs (who follows whom, who blocks whom) and secondary indices. As of April 2010, the Twitter FlockDB cluster stores 13+ billion edges and sustains peak traffic of 20k writes/second and 100k reads/second.
2. FlockDB is much simpler than other graph databases such as neo4j because it tries to solve fewer problems. It scales horizontally and is designed for on-line, low-latency, high throughput environments such as web-sites.