300 Tab Bar Icons for iPhone and iPad : This icons optimized for iOS 7 - iOS 8 Tab Bar, but icons can be used not only on Tab Bar or iOS. They have various uses and they are fully resizable.

IMPICONS - Modern Flat style Free Icon Set - Freebie No: 116

40 Free Icons (Psd, Ai) : Just freebie icon pack.

Google Material Design : Visual design, specification guidelines, product branding, and system iconography for Google and Android’s new design language

百度金融 - 安全、专业、全面的综合金融服务平台

80个线性图标（PSD + AI + Webfont）

65 free icons : 65 vector icons in 3 formats: Psd, Ai, Eps.

Web design freebies, Infinity - Free Space Icons

icon for a new project on Behance