KEY FEATURES: - Supports boost the sound files volume up to 1000%. - Supports decrease or mute sound too. - Supports video, audio, music, movie, memo, voice, audio book etc. - Powerful audo equalizer with professional preset sound effects. - Improves the sound quality with latest technologies for maximum sound amplification. - Simple, small, clean, user-friendly and efficient! - You can enjoy more immersive sound than ever. - One-touch operation. SUBSCRIPTION INFORMATION: - Subscribe to get access to all the Premium features - Weekly or yearly Premium Pass - Features: Premium for Full Access. Boost all volume up to 1000%; No time limit; Ads free. - Free trial subscription is automatically renewed unless cancelled 24 hours before the renewal - Payment will be charged to iTunes Account at confirmation of purchase - Account will be charged for renewal within 24-hours prior to the end of the current period, at the same price - Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable. - Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user’s Account Settings after purchase Terms of Use: https://jinyina1996.wixsite.com/volboom/terms-of-use Privacy Policy: https://jinyina1996.wixsite.com/volboom/privacy-policy *Price are equal to the value that "Apple's App Store Matrix" determines is the equivalent of the subscription price in $USD.