In terms of market share, Observer is clearly lagging behind, losing to WebProspector in all segments.
WebProspector has better usage coverage in more websites categories. Including Business & Industry, Internet & Telecom, Marketing & Advertising, Computer & Electronics and 43 other categories.
Observer is leading in People & Society, Travel, Web Design, Photography and 11 other categories.
WebProspector is leading in most countries, including Germany, Switzerland, Austria, Belgium and 12 other countries.
Observer is leading in United States, Russia, China, Brazil and 4 other countries.