Hi コウ, having lag in our app is not the experience we want for you. We're really sorry that you've experienced this. Kindly send us an email at support@soundtrap.com along with the device's operating system that you're using. Rest assured that we'll keep an eye out for your email :)
We appreciate your honest feedback and decent rating, れい明朝! We'd love to assist you with the issue you're encountering. Kindly send us an email at support@soundtrap.com. Hope to hear from you soon.