Observer
2 websites

Observer is free to use

http://observerapp.com/

Observer is a web analytic tool developed by Ludwig Pettersson. Observer also includes a toolbar that lets you view your analytics no matter what site you are on.

VS

PercentMobile
10 websites

PercentMobile offers both free and paid options

http://percentmobile.com/mobileanalytics

QR Codes, NFC Tags, and Real-world Analytics by Delivr. Delivr is a hosted service that provides QR Code and NFC Tag creation, management, and tracking .

Market Share by Top Websites

2 In terms of market share, Observer is clearly lagging behind, losing to PercentMobile in all segments.

Websites Categories

1 PercentMobile has better usage coverage in more websites categories. Including Arts & Entertainment, Community & Society and Hobbies & Leisure.

2 Observer is leading in Computers Electronics & Technology.

Geography

1 PercentMobile is leading in most countries, including Spain, United Kingdom, Argentina and Ecuador.

2 Observer is leading in Russia.