FAQ
How does this compare with GPS, Cell Id positioning etc?
At no point does Snowball need to know the Geographical position of the user. Hence it does not need to rely on the GPS or Cellular positioning capabilities of the device or network.
But first some background…
The story of a location based service tends to start out by determining a user’s geographical location, and then providing relevant information to the user based on it. Unfortunately, position fixing technologies (and applications that rely on them) have a number of inherent problems:
GPS
- A GS receiver works well in a moving vehicle because “loss of signal” and “timing errors” can be averaged out over time. However GPS works poorly when the user is stationary, in a densely packed environment (i.e. a city), or indoors - making it entirely unsuitable for many consumer targeted applications.
- A GPS receiver may require considerable time to obtain its first position fix after a cold start. This has a large negative impact on location based applications, because they usually need to determine their position before they can provide information to the user.
- Limited availability of GPS hardware on devices. You can’t build a social network around an application if most people can’t participate.
Cellular positioning
- A simple cell tower id based position fix can represent an area covering many miles (although this improves in urban area).
- More accurate systems based on cell tower delay and triangulation are provided and controlled by the cellular operators, who distribute this information through aggregators.
- Often creating cost hurdles, reducing positional accuracy (to protect privacy) or adding complexity in the form of constant user approval for the tracking service.
- Positing technologies and APIs are highly fragmented, meaning your location based service will work before you get on the plane in country (a), but will break down as soon as you get off the plane in country (b) – exactly when you need it most!
Privacy
Users don’t like being tracked, and in many countries it is against the law for private companies to handle and pass on sensitive personal information. Hence when developing a “positioning based” service, important safeguards need to be implemented to stop a user’s position being given to the wrong third party, and perhaps more importantly, reassurances need to be given to the user to convince them that these safeguards exist!
Performance
Instead of competing against GPS, Snowball provides an alternative technology with very different yet highly complementary dynamics. This approach has many benefits:
- How do you rank services by how easy they are to get to?
Because Snowball networks are derived from human movement, they automatically incorporate elements such as transport infrastructure (roads, busses, trains) or impassable barriers (river crossings) into proximity estimates. - How can two users on a moving vehicle (e.g. bus, train, cruse ship) find each other?
Snowball networks ignore geographical position and instead model the relative proximity of devices with one another. Hence a user could use Snowball to find another mobile Quake player on the same bus and then “DeathMatch” all the way to their destination. - How scalable is a Snowball network?
Server based systems require proportionally more computing power for each extra user who joins the system. This makes them unsuited for large scale real time applications, where users might want to be alerted when certain other users are nearby.Snowball is a peer-to-peer network which leans on its participating nodes for computing power, and can thereby be extended indefinitely. - How can I use Snowball when I don’t have connectivity?
Snowball applications keep working even after you lose data connectivity. This is possible because the Snowball API is connected to the on device ad database, which handles all application requests. Snowball will then refresh this information the next time an opportunity presents itself.
Hence you can still search for info when your train goes underground!
