Crowd Flow
  • Small Business

News from the Online Casino Malaysia challenge

  • admin
  • January 21, 2023
  18 months have passed since we told you on Online Casino Malaysia about the challenge launched by Tom Dwan, the 24-year-old online poker genius. We remind you of the rules and stakes of…
View Post
Share
  • Small Business

Wednesday morning slot gacor…

  • admin
  • January 18, 2023
  I have good news to report too. I’m officially getting better at pool. 🙂 I’m now ranked a 3 instead of a 2 by the slot gacor. I’ve won my last two or three matches in…
View Post
Share
  • Small Business

먹튀폴리스 먹튀검증games free

  • admin
  • October 28, 2022
  If you are looking to play 먹튀폴리스 먹튀검증games free, then you should always go with the online reviews which have posted by other players. Reviews can tell everything about the online…
View Post
Share
  • game

Bet Direct Slot Gacor WPT final approaches

  • admin
  • October 6, 2022
This year the World Slot Gacor Tour finals will take place at The Bellagio, Las Vegas. Bet Direct Poker players still have a chance to win their seat, but time is quickly running out.…
View Post
Share
  • Small Business

Third Day’s Play at the situs judi online Tournament

  • admin
  • September 28, 2022
  The third day’s play at the situs judi online began with 72 participants. Each player was assured of a minimum of $7,500 in prize money. Many top ranking players remained in the…
View Post
Share
  • Small Business

Higher Stakes = Better Results?

  • admin
  • September 27, 2022
Since my last post, I’ve played a total of two tournaments at Online Casino Malaysia, and none anywhere else. The two that I played were tournaments that I wouldn’t have played in last week…
View Post
Share
  • Small Business

Top 5 strangest places on Earth

  • admin
  • September 14, 2022
  The Great Blue Hole The Great Blue Hole is a large submarine sinkhole off the coast of Belize on the Caribbean Sea. Its diameter is 300 m and its depth is more than 120 m. Its unique…
View Post
Share
  • Business

Sarah Palin to Guest Host Today Show

  • admin
  • September 13, 2022
Former political figure Sarah Palin has signed up to co-host the Today show this week for some reason, NBC reports. She will do the honors tomorrow (Tuesday).According to a message posted on…
View Post
Share
  • game

How to Enjoy winning369 Online Easily

  • admin
  • August 12, 2022
  How you can play poker online is one of challenging game among all the particular games that exist upon the IDNPLAY server. This kind of is because of just how to learn using various…
View Post
Share
  • game

Omens… sbo Lots of ‘Em… All Bad

  • admin
  • July 14, 2022
  Where did I go wrong? I suppose it started with my overly arrogant “How to Win at Craps” post. I forgot rule number one about casino gambling. It doesn’t matter what…
View Post
Share
  • Home
  • About Us
  • Connect With us
  • Privacy Policy
  • Categories
Subscribe
Crowd Flow
Crowd Flow
  • Home
  • Connect With us
  • About Us
  • Small Business
  • Education
  • Issues
  • Trending
  • Latest
  • Business
  • Local Government Aid
  • Spending
  • Education
  • Small Business

Deeper insights into Apple’s “GPS”

  • September 3, 2021
  • admin
  • No comments
  • 3 minute read
Total
0
Shares
0
0
0

Some iPhone Apps need to know the location of your iPhone, e.g. the camera, Google maps, Facebook Places, Foursquare, etc.

“And that’s why the iPhones has GPS!”

Well, basically: Yes – but GPS has some disadvantages:

  • battery drain: GPS uses a lot of energy
  • mostly useless in towns and buildings: GPS needs to receive very weak satellite signals
  • very slow: GPS needs up to 12.5 minutes to initialize

GPS was not developed to work in a cell phone. So we need some additional technologies like assisted GPS or even better:

WPS or WiFi Positioning System

WPS was developed by “Skyhook Wireless” and uses information from surrounding wireless networks. So here’s the idea:

If you want to know your location the iPhone starts listening to the surrounding WiFi signals. Usually it receives some IDs (MAC addresses) from wireless access points nearby. In case th iPhone knows the position of these access points it can estimate its own location – in just a few seconds.

Unfortunately this system needs a map of almost all WiFi networks to work properly. That seems to be impossible but actually the iPhones are creating this map.

 

Step1: iPhones are gathering data

Every iPhone is looking for surrounding WiFi and cell networks.

(According to Apple, only if you use a location App but we could not verify this claim yet.)

The collected data is stored locally in the consolidated.db (WifiLocationHarvest) with:

  • information about the WiFi access point (MAC, channel, hidden, RSSI)
  • information about the collecting iPhone (latitude, longitude, altitude, horizontal and vertical accuracy, speed, course)
  • some additional information (timestamp, age, used App, confidence)

This is also done with data about surrounding cell networks (CellLocationHarvest and CdmaCellLocationHarvest).

(Since all iPhones flush their data every 12 hours, an average dataset covers 6 hours. Since this video covers 24 hours, the shown activity corresponds to approximately 10 iPhones. Now guess, what it would look like for 10 000 iPhones!)

Step2: Apple creates a map

Millions of iPhones are collecting data about WiFi and cell networks and sending this data “back home” to Apple. Obviously Apple collects this data and tries to create a map of all known WiFi access points and cell areas.

Therefore they have to estimate the location and the size of each WiFi and cell area. If a WiFi device is found in different towns, it’s probably a mobile access point (e.g. MiFi).

We would love to visualize how Apple is try to combine the collected data to a WiFi and cell map, but unfortunately we do not have enough data about this process.

At least we could find some artifacts of Apples mapping algorithm. E.g. here in one of our earlier WiFi heatmaps of Berlin you can see a horizontal cut in the lower half of the map:

The latest version of the WiFi heatmap doesn’t show any artifacts:

But you can still see some artifacts in the latest heatmap of Germany:


But here is something interesting about the cell coverage.
On the left side you can see the position of a cell tower and its 3 cells (blue, yellow and red) with an (estimated) radius of 2km.
On the right side we added Apples estimated coverage of these three cells.

Step 3: iPhones download parts of the map

If an iPhone is in an unknown area it requests data about the surrounding WiFi and cells to improve the location accuracy. Then Apple sends the results. The query results basically look like this:


(scale unit: meters)

If an iPhone with activated location App travels through a new region, it constantly updates the local database

 

6 Responses to Deeper insights into Apple’s “GPS”

If I’m not mistaken, Google’s Android platform does almost this exact same thing (if you choose to enable it when activating your device). It was my understanding that this was the biggest technical advantage of having a large % of the smartphone OS market, that your given OS would have more accurate location-enabled data that didn’t depend on actual GPS.

It’s nice to see some actual visualizations of this data, you guys rock

Total
0
Shares
Share 0
Tweet 0
Pin it 0
admin

Next Article
  • Business
  • Education

First glimpse of worldwide cell phone coverage

  • September 3, 2021
  • admin
View Post
You May Also Like
View Post
  • Small Business

News from the Online Casino Malaysia challenge

  • admin
  • January 21, 2023
View Post
  • Small Business

Wednesday morning slot gacor…

  • admin
  • January 18, 2023
View Post
  • Small Business

먹튀폴리스 먹튀검증games free

  • admin
  • October 28, 2022
View Post
  • Small Business

Third Day’s Play at the situs judi online Tournament

  • admin
  • September 28, 2022
View Post
  • Small Business

Higher Stakes = Better Results?

  • admin
  • September 27, 2022
View Post
  • Small Business

Top 5 strangest places on Earth

  • admin
  • September 14, 2022
View Post
  • Small Business

The “Hole-Card” Cam slothoki

  • admin
  • July 7, 2022
View Post
  • Small Business

Anti-Aging Skin Care Tips

  • admin
  • June 15, 2022

Recent Posts

  • News from the Online Casino Malaysia challenge
  • Wednesday morning slot gacor…
  • 먹튀폴리스 먹튀검증games free
  • Bet Direct Slot Gacor WPT final approaches
  • Third Day’s Play at the situs judi online Tournament

Archives

  • January 2023
  • October 2022
  • September 2022
  • August 2022
  • July 2022
  • June 2022
  • May 2022
  • April 2022
  • March 2022
  • February 2022
  • January 2022
  • December 2021
  • November 2021
  • October 2021
  • September 2021

Categories

  • Business
  • Education
  • game
  • Issues
  • Local Government Aid
  • Small Business
  • Spending
  • Trending
  • Small Business

News from the Online Casino Malaysia challenge

  • admin
  • January 21, 2023
  18 months have passed since we told you on Online Casino Malaysia about the challenge launched by Tom Dwan, the 24-year-old online poker genius. We remind you of the rules and stakes of…
View Post
Share
  • Small Business

Wednesday morning slot gacor…

  • admin
  • January 18, 2023
  I have good news to report too. I’m officially getting better at pool. 🙂 I’m now ranked a 3 instead of a 2 by the slot gacor. I’ve won my last two or three matches in…
View Post
Share
  • Small Business

먹튀폴리스 먹튀검증games free

  • admin
  • October 28, 2022
  If you are looking to play 먹튀폴리스 먹튀검증games free, then you should always go with the online reviews which have posted by other players. Reviews can tell everything about the online…
View Post
Share
  • game

Bet Direct Slot Gacor WPT final approaches

  • admin
  • October 6, 2022
This year the World Slot Gacor Tour finals will take place at The Bellagio, Las Vegas. Bet Direct Poker players still have a chance to win their seat, but time is quickly running out.…
View Post
Share
  • Small Business

Third Day’s Play at the situs judi online Tournament

  • admin
  • September 28, 2022
  The third day’s play at the situs judi online began with 72 participants. Each player was assured of a minimum of $7,500 in prize money. Many top ranking players remained in the…
View Post
Share
  • Small Business

Higher Stakes = Better Results?

  • admin
  • September 27, 2022
Since my last post, I’ve played a total of two tournaments at Online Casino Malaysia, and none anywhere else. The two that I played were tournaments that I wouldn’t have played in last week…
View Post
Share
  • Small Business

Top 5 strangest places on Earth

  • admin
  • September 14, 2022
  The Great Blue Hole The Great Blue Hole is a large submarine sinkhole off the coast of Belize on the Caribbean Sea. Its diameter is 300 m and its depth is more than 120 m. Its unique…
View Post
Share
  • Business

Sarah Palin to Guest Host Today Show

  • admin
  • September 13, 2022
Former political figure Sarah Palin has signed up to co-host the Today show this week for some reason, NBC reports. She will do the honors tomorrow (Tuesday).According to a message posted on…
View Post
Share
  • game

How to Enjoy winning369 Online Easily

  • admin
  • August 12, 2022
  How you can play poker online is one of challenging game among all the particular games that exist upon the IDNPLAY server. This kind of is because of just how to learn using various…
View Post
Share
  • game

Omens… sbo Lots of ‘Em… All Bad

  • admin
  • July 14, 2022
  Where did I go wrong? I suppose it started with my overly arrogant “How to Win at Craps” post. I forgot rule number one about casino gambling. It doesn’t matter what…
View Post
Share
  • Small Business
News from the Online Casino Malaysia challenge
    • Small Business
    Wednesday morning slot gacor…
      1. Your Link
      2. Your Link
      3. Your Link
      4. Your Link
      • Home
      • About Us
      • Connect With us
      • Privacy Policy
      • Categories
        • Trending
        • Issues
        • Latest
        • Spending
        • Small Business
        • Local Government Aid
        • Education
        • Business
      Crowd Flow
      • Home
      • About Us
      • Connect With us
      • Privacy Policy
      • Categories
      © 2021 Crowd Flow. Trademarks and brands are the property of their respective owners.

      Input your search keywords and press Enter.