diff --git a/gamecontext.go b/gamecontext.go
index d83c48ded..75212ffad 100644
--- a/gamecontext.go
+++ b/gamecontext.go
@@ -77,7 +77,7 @@ func IsGamepadButtonPressed(id int, button GamepadButton) bool {
 func NewImage(width, height int, filter Filter) (*Image, error) {
 	var img *Image
 	var err error
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		var texture *graphics.Texture
 		var framebuffer *graphics.Framebuffer
 		texture, err = graphics.NewTexture(c, width, height, glFilter(c, filter))
@@ -108,7 +108,7 @@ func NewImage(width, height int, filter Filter) (*Image, error) {
 func NewImageFromImage(img image.Image, filter Filter) (*Image, error) {
 	var eimg *Image
 	var err error
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		var texture *graphics.Texture
 		var framebuffer *graphics.Framebuffer
 		texture, err = graphics.NewTextureFromImage(c, img, glFilter(c, filter))
diff --git a/genkeys.go b/genkeys.go
index 8502d8424..63aac4f4b 100644
--- a/genkeys.go
+++ b/genkeys.go
@@ -77,7 +77,6 @@ const ebitenKeysTmpl = `{{.License}}
 
 package ebiten
 
-
 import (
 	"github.com/hajimehoshi/ebiten/internal/ui"
 )
diff --git a/image.go b/image.go
index 707ac2b2d..9c1f3850d 100644
--- a/image.go
+++ b/image.go
@@ -19,7 +19,6 @@ import (
 	"fmt"
 	"github.com/hajimehoshi/ebiten/internal/graphics"
 	"github.com/hajimehoshi/ebiten/internal/graphics/internal/opengl"
-	"github.com/hajimehoshi/ebiten/internal/ui"
 	"image"
 	"image/color"
 	"math"
@@ -53,7 +52,7 @@ func (i *Image) Fill(clr color.Color) (err error) {
 	g := float64(cg) / max
 	b := float64(cb) / max
 	a := float64(ca) / max
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		// TODO: Change to pass color.Color
 		err = i.framebuffer.Fill(c, r, g, b, a)
 	})
@@ -95,7 +94,7 @@ func (i *Image) DrawImage(image *Image, options *DrawImageOptions) (err error) {
 	}
 	w, h := image.Size()
 	quads := &textureQuads{parts: parts, width: w, height: h}
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		err = i.framebuffer.DrawTexture(c, image.texture, quads, &options.GeoM, &options.ColorM)
 	})
 	return
@@ -109,7 +108,7 @@ func (i *Image) DrawLine(x0, y0, x1, y1 int, clr color.Color) error {
 // DrawLines draws lines.
 func (i *Image) DrawLines(lines Lines) (err error) {
 	i.pixels = nil
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		err = i.framebuffer.DrawLines(c, lines)
 	})
 	return
@@ -133,7 +132,7 @@ func (i *Image) DrawFilledRect(x, y, width, height int, clr color.Color) error {
 // DrawFilledRects draws filled rectangles on the image.
 func (i *Image) DrawFilledRects(rects Rects) (err error) {
 	i.pixels = nil
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		err = i.framebuffer.DrawFilledRects(c, rects)
 	})
 	return
@@ -155,7 +154,7 @@ func (i *Image) ColorModel() color.Model {
 // This method loads pixels from VRAM to system memory if necessary.
 func (i *Image) At(x, y int) color.Color {
 	if i.pixels == nil {
-		ui.Use(func(c *opengl.Context) {
+		useGLContext(func(c *opengl.Context) {
 			var err error
 			i.pixels, err = i.framebuffer.Pixels(c)
 			if err != nil {
@@ -184,7 +183,7 @@ func (i *Image) ReplacePixels(p []uint8) error {
 		return errors.New(fmt.Sprintf("p's length must be %d", l))
 	}
 	var err error
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		err = i.texture.ReplacePixels(c, p)
 	})
 	return err
diff --git a/internal/ui/input_glfw.go b/internal/ui/input_glfw.go
index 772676c32..a69b1a049 100644
--- a/internal/ui/input_glfw.go
+++ b/internal/ui/input_glfw.go
@@ -21,6 +21,10 @@ import (
 	"math"
 )
 
+func UpdateInput(window *glfw.Window, scale int) error {
+	return currentInput.update(window, scale)
+}
+
 var glfwMouseButtonToMouseButton = map[glfw.MouseButton]MouseButton{
 	glfw.MouseButtonLeft:   MouseButtonLeft,
 	glfw.MouseButtonRight:  MouseButtonRight,
diff --git a/internal/ui/input_js.go b/internal/ui/input_js.go
index 1589241e4..aa0306ed0 100644
--- a/internal/ui/input_js.go
+++ b/internal/ui/input_js.go
@@ -20,7 +20,11 @@ import (
 	"github.com/gopherjs/gopherjs/js"
 )
 
-func (i *input) keyDown(key int) {
+func CurrentInput() *input {
+	return &currentInput
+}
+
+func (i *input) KeyDown(key int) {
 	k, ok := keyCodeToKey[key]
 	if !ok {
 		return
@@ -28,7 +32,7 @@ func (i *input) keyDown(key int) {
 	i.keyPressed[k] = true
 }
 
-func (i *input) keyUp(key int) {
+func (i *input) KeyUp(key int) {
 	k, ok := keyCodeToKey[key]
 	if !ok {
 		return
@@ -36,7 +40,7 @@ func (i *input) keyUp(key int) {
 	i.keyPressed[k] = false
 }
 
-func (i *input) mouseDown(button int) {
+func (i *input) MouseDown(button int) {
 	p := &i.mouseButtonPressed
 	switch button {
 	case 0:
@@ -48,7 +52,7 @@ func (i *input) mouseDown(button int) {
 	}
 }
 
-func (i *input) mouseUp(button int) {
+func (i *input) MouseUp(button int) {
 	p := &i.mouseButtonPressed
 	switch button {
 	case 0:
@@ -60,11 +64,11 @@ func (i *input) mouseUp(button int) {
 	}
 }
 
-func (i *input) setMouseCursor(x, y int) {
+func (i *input) SetMouseCursor(x, y int) {
 	i.cursorX, i.cursorY = x, y
 }
 
-func (i *input) updateGamepads() {
+func (i *input) UpdateGamepads() {
 	nav := js.Global.Get("navigator")
 	if nav.Get("getGamepads") == js.Undefined {
 		return
diff --git a/run.go b/run.go
index 68a7f2a38..e6b4f8542 100644
--- a/run.go
+++ b/run.go
@@ -17,7 +17,6 @@ package ebiten
 import (
 	"github.com/hajimehoshi/ebiten/internal/audio"
 	"github.com/hajimehoshi/ebiten/internal/graphics/internal/opengl"
-	"github.com/hajimehoshi/ebiten/internal/ui"
 	"time"
 )
 
@@ -38,14 +37,15 @@ func CurrentFPS() float64 {
 // but this is not strictly guaranteed.
 // If you need to care about time, you need to check current time every time f is called.
 func Run(f func(*Image) error, width, height, scale int, title string) error {
-	actualScale, err := ui.Start(width, height, scale, title)
+	ui := currentUI
+	actualScale, err := ui.start(width, height, scale, title)
 	if err != nil {
 		return err
 	}
-	defer ui.Terminate()
+	defer ui.terminate()
 
 	var graphicsContext *graphicsContext
-	ui.Use(func(c *opengl.Context) {
+	useGLContext(func(c *opengl.Context) {
 		graphicsContext, err = newGraphicsContext(c, width, height, actualScale)
 	})
 	if err != nil {
@@ -55,10 +55,10 @@ func Run(f func(*Image) error, width, height, scale int, title string) error {
 	frames := 0
 	t := time.Now().UnixNano()
 	for {
-		if err := ui.DoEvents(); err != nil {
+		if err := ui.doEvents(); err != nil {
 			return err
 		}
-		if ui.IsClosed() {
+		if ui.isClosed() {
 			return nil
 		}
 		if err := graphicsContext.preUpdate(); err != nil {
@@ -72,7 +72,7 @@ func Run(f func(*Image) error, width, height, scale int, title string) error {
 		}
 		// TODO: I'm not sure this is 'Update'. Is 'Tick' better?
 		audio.Update()
-		ui.SwapBuffers()
+		ui.swapBuffers()
 		if err != nil {
 			return err
 		}
diff --git a/internal/ui/ui_glfw.go b/ui_glfw.go
similarity index 78%
rename from internal/ui/ui_glfw.go
rename to ui_glfw.go
index ca2b1d9a5..e746bd5ef 100644
--- a/internal/ui/ui_glfw.go
+++ b/ui_glfw.go
@@ -14,44 +14,29 @@
 
 // +build !js
 
-package ui
+package ebiten
 
 import (
 	"fmt"
 	glfw "github.com/go-gl/glfw3"
 	"github.com/hajimehoshi/ebiten/internal/audio"
 	"github.com/hajimehoshi/ebiten/internal/graphics/internal/opengl"
+	"github.com/hajimehoshi/ebiten/internal/ui"
 	"runtime"
 	"time"
 )
 
-var current *ui
+var currentUI *userInterface
 
-func Use(f func(*opengl.Context)) {
+func useGLContext(f func(*opengl.Context)) {
 	ch := make(chan struct{})
-	current.funcs <- func() {
+	currentUI.funcs <- func() {
 		defer close(ch)
-		f(current.glContext)
+		f(currentUI.glContext)
 	}
 	<-ch
 }
 
-func DoEvents() error {
-	return current.doEvents()
-}
-
-func Terminate() {
-	current.terminate()
-}
-
-func IsClosed() bool {
-	return current.isClosed()
-}
-
-func SwapBuffers() {
-	current.swapBuffers()
-}
-
 func init() {
 	runtime.LockOSThread()
 
@@ -69,7 +54,7 @@ func init() {
 		panic(err)
 	}
 
-	u := &ui{
+	u := &userInterface{
 		window: window,
 		funcs:  make(chan func()),
 	}
@@ -85,17 +70,17 @@ func init() {
 
 	audio.Init()
 
-	current = u
+	currentUI = u
 }
 
-type ui struct {
+type userInterface struct {
 	window    *glfw.Window
 	scale     int
 	glContext *opengl.Context
 	funcs     chan func()
 }
 
-func Start(width, height, scale int, title string) (actualScale int, err error) {
+func (u *userInterface) start(width, height, scale int, title string) (actualScale int, err error) {
 	monitor, err := glfw.GetPrimaryMonitor()
 	if err != nil {
 		return 0, err
@@ -108,8 +93,7 @@ func Start(width, height, scale int, title string) (actualScale int, err error)
 	y := (videoMode.Height - height*scale) / 3
 
 	ch := make(chan struct{})
-	ui := current
-	window := ui.window
+	window := u.window
 	window.SetFramebufferSizeCallback(func(w *glfw.Window, width, height int) {
 		close(ch)
 	})
@@ -131,7 +115,7 @@ func Start(width, height, scale int, title string) (actualScale int, err error)
 		}
 	}
 
-	ui.scale = scale
+	u.scale = scale
 
 	// For retina displays, recalculate the scale with the framebuffer size.
 	windowWidth, _ := window.GetFramebufferSize()
@@ -142,16 +126,16 @@ func Start(width, height, scale int, title string) (actualScale int, err error)
 	return actualScale, nil
 }
 
-func (u *ui) pollEvents() error {
+func (u *userInterface) pollEvents() error {
 	glfw.PollEvents()
-	return currentInput.update(u.window, u.scale)
+	return ui.UpdateInput(u.window, u.scale)
 }
 
-func (u *ui) doEvents() error {
+func (u *userInterface) doEvents() error {
 	if err := u.pollEvents(); err != nil {
 		return err
 	}
-	for current.window.GetAttribute(glfw.Focused) == 0 {
+	for u.window.GetAttribute(glfw.Focused) == 0 {
 		time.Sleep(time.Second / 60)
 		if err := u.pollEvents(); err != nil {
 			return err
@@ -160,14 +144,14 @@ func (u *ui) doEvents() error {
 	return nil
 }
 
-func (u *ui) terminate() {
+func (u *userInterface) terminate() {
 	glfw.Terminate()
 }
 
-func (u *ui) isClosed() bool {
+func (u *userInterface) isClosed() bool {
 	return u.window.ShouldClose()
 }
 
-func (u *ui) swapBuffers() {
+func (u *userInterface) swapBuffers() {
 	u.window.SwapBuffers()
 }
diff --git a/internal/ui/ui_js.go b/ui_js.go
similarity index 88%
rename from internal/ui/ui_js.go
rename to ui_js.go
index e48c8b85b..ac00dbb07 100644
--- a/internal/ui/ui_js.go
+++ b/ui_js.go
@@ -14,26 +14,31 @@
 
 // +build js
 
-package ui
+package ebiten
 
 import (
 	"github.com/gopherjs/gopherjs/js"
 	"github.com/gopherjs/webgl"
 	"github.com/hajimehoshi/ebiten/internal/audio"
 	"github.com/hajimehoshi/ebiten/internal/graphics/internal/opengl"
+	"github.com/hajimehoshi/ebiten/internal/ui"
 	"strconv"
 )
 
 var canvas js.Object
 var context *opengl.Context
 
+type userInterface struct{}
+
+var currentUI = &userInterface{}
+
 // TODO: This returns true even when the browser is not active.
 // The current behavior causes sound noise...
 func shown() bool {
 	return !js.Global.Get("document").Get("hidden").Bool()
 }
 
-func Use(f func(*opengl.Context)) {
+func useGLContext(f func(*opengl.Context)) {
 	f(context)
 }
 
@@ -47,24 +52,24 @@ func vsync() {
 	<-ch
 }
 
-func DoEvents() error {
+func (*userInterface) doEvents() error {
 	vsync()
 	for !shown() {
 		vsync()
 	}
-	currentInput.updateGamepads()
+	ui.CurrentInput().UpdateGamepads()
 	return nil
 }
 
-func Terminate() {
+func (*userInterface) terminate() {
 	// Do nothing.
 }
 
-func IsClosed() bool {
+func (*userInterface) isClosed() bool {
 	return false
 }
 
-func SwapBuffers() {
+func (*userInterface) swapBuffers() {
 	// Do nothing.
 }
 
@@ -127,25 +132,25 @@ func init() {
 	canvas.Call("addEventListener", "keydown", func(e js.Object) {
 		e.Call("preventDefault")
 		code := e.Get("keyCode").Int()
-		currentInput.keyDown(code)
+		ui.CurrentInput().KeyDown(code)
 	})
 	canvas.Call("addEventListener", "keyup", func(e js.Object) {
 		e.Call("preventDefault")
 		code := e.Get("keyCode").Int()
-		currentInput.keyUp(code)
+		ui.CurrentInput().KeyUp(code)
 	})
 
 	// Mouse
 	canvas.Call("addEventListener", "mousedown", func(e js.Object) {
 		e.Call("preventDefault")
 		button := e.Get("button").Int()
-		currentInput.mouseDown(button)
+		ui.CurrentInput().MouseDown(button)
 		setMouseCursorFromEvent(e)
 	})
 	canvas.Call("addEventListener", "mouseup", func(e js.Object) {
 		e.Call("preventDefault")
 		button := e.Get("button").Int()
-		currentInput.mouseUp(button)
+		ui.CurrentInput().MouseUp(button)
 		setMouseCursorFromEvent(e)
 	})
 	canvas.Call("addEventListener", "mousemove", func(e js.Object) {
@@ -160,14 +165,14 @@ func init() {
 	// TODO: Need to create indimendent touch functions?
 	canvas.Call("addEventListener", "touchstart", func(e js.Object) {
 		e.Call("preventDefault")
-		currentInput.mouseDown(0)
+		ui.CurrentInput().MouseDown(0)
 		touches := e.Get("changedTouches")
 		touch := touches.Index(0)
 		setMouseCursorFromEvent(touch)
 	})
 	canvas.Call("addEventListener", "touchend", func(e js.Object) {
 		e.Call("preventDefault")
-		currentInput.mouseUp(0)
+		ui.CurrentInput().MouseUp(0)
 		touches := e.Get("changedTouches")
 		touch := touches.Index(0)
 		setMouseCursorFromEvent(touch)
@@ -193,7 +198,7 @@ func setMouseCursorFromEvent(e js.Object) {
 	x, y := e.Get("clientX").Int(), e.Get("clientY").Int()
 	x -= rect.Get("left").Int()
 	y -= rect.Get("top").Int()
-	currentInput.setMouseCursor(x/scale, y/scale)
+	ui.CurrentInput().SetMouseCursor(x/scale, y/scale)
 }
 
 func devicePixelRatio() int {
@@ -205,7 +210,7 @@ func devicePixelRatio() int {
 	return ratio
 }
 
-func Start(width, height, scale int, title string) (actualScale int, err error) {
+func (*userInterface) start(width, height, scale int, title string) (actualScale int, err error) {
 	doc := js.Global.Get("document")
 	doc.Set("title", title)
 	actualScale = scale * devicePixelRatio()