消防設備士第4類【甲乙対応】（過去問ドリル) vs Duolingo: Language Lessons
A data-backed head-to-head — estimated revenue, downloads, ratings and pricing side by side, from live App Store signals. Updated continuously.
Revenue / mo
$40–$300
$12M–$40M
Downloads / mo
100–500
6.6M–27M
Rating
★ 3.60 (—)
★ 4.73 (48M)
Pricing
Free + IAP
Free + IAP
Category
Education
Education
Released
—
13.2y ago
Verdict: Duolingo: Language Lessons earns more — an estimated $12M–$40M/mo, versus $40–$300/mo for 消防設備士第4類【甲乙対応】（過去問ドリル).