diff --git a/mobile/src/main/res/values/dimen.xml b/mobile/src/main/res/values/dimen.xml
index e25dae51..415496c2 100644
--- a/mobile/src/main/res/values/dimen.xml
+++ b/mobile/src/main/res/values/dimen.xml
@@ -1,7 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
     <dimen name="profile_item_max_width">480dp</dimen>
-    <dimen name="icon_list_item_padding">16dp</dimen>
+    <dimen name="qr_code_size">250dp</dimen>
+    <dimen name="margin_small">8dp</dimen>
     <!-- TODO: Remove when this issue is fixed: https://github.com/JorgeCastilloPrz/FABProgressCircle/issues/19 -->
     <dimen name="fab_margin_top">-44dp</dimen>
 </resources>
diff --git a/mobile/src/main/scala/com/github/shadowsocks/MainActivity.scala b/mobile/src/main/scala/com/github/shadowsocks/MainActivity.scala
index 7bab1a25..aad23528 100644
--- a/mobile/src/main/scala/com/github/shadowsocks/MainActivity.scala
+++ b/mobile/src/main/scala/com/github/shadowsocks/MainActivity.scala
@@ -309,7 +309,7 @@ class MainActivity extends Activity with ServiceBoundContext with Drawer.OnDrawe
     })
     fab.setOnLongClickListener(_ => {
       Utils.positionToast(Toast.makeText(this, if (state == State.CONNECTED) R.string.stop else R.string.connect,
-        Toast.LENGTH_SHORT), fab, getWindow, 0, Utils.dpToPx(this, 8)).show()
+        Toast.LENGTH_SHORT), fab, getWindow, 0, getResources.getDimensionPixelOffset(R.dimen.margin_small)).show()
       true
     })
 
diff --git a/mobile/src/main/scala/com/github/shadowsocks/ProfilesFragment.scala b/mobile/src/main/scala/com/github/shadowsocks/ProfilesFragment.scala
index bc5b4fbe..517950e6 100644
--- a/mobile/src/main/scala/com/github/shadowsocks/ProfilesFragment.scala
+++ b/mobile/src/main/scala/com/github/shadowsocks/ProfilesFragment.scala
@@ -55,7 +55,7 @@ final class ProfilesFragment extends ToolbarFragment with Toolbar.OnMenuItemClic
 
   private val cardButtonLongClickListener: OnLongClickListener = view => {
     Utils.positionToast(Toast.makeText(getActivity, view.getContentDescription, Toast.LENGTH_SHORT), view,
-      getActivity.getWindow, 0, Utils.dpToPx(getActivity, 8)).show()
+      getActivity.getWindow, 0, getResources.getDimensionPixelOffset(R.dimen.margin_small)).show()
     true
   }
 
@@ -129,7 +129,7 @@ final class ProfilesFragment extends ToolbarFragment with Toolbar.OnMenuItemClic
           val params =
             new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)
           params.gravity = Gravity.CENTER_HORIZONTAL
-          params.setMargins(0, Utils.dpToPx(getActivity, 8), 0, 0)
+          params.setMargins(0, getResources.getDimensionPixelOffset(R.dimen.margin_small), 0, 0)
           adView = new NativeExpressAdView(getActivity)
           adView.setLayoutParams(params)
           adView.setAdUnitId("ca-app-pub-9097031975646651/5224027521")
diff --git a/mobile/src/main/scala/com/github/shadowsocks/QRCodeDialog.scala b/mobile/src/main/scala/com/github/shadowsocks/QRCodeDialog.scala
index 255444dc..66317aa8 100644
--- a/mobile/src/main/scala/com/github/shadowsocks/QRCodeDialog.scala
+++ b/mobile/src/main/scala/com/github/shadowsocks/QRCodeDialog.scala
@@ -27,7 +27,6 @@ import android.nfc.{NdefMessage, NdefRecord, NfcAdapter}
 import android.os.Bundle
 import android.view.{LayoutInflater, View, ViewGroup}
 import android.widget.{ImageView, LinearLayout}
-import com.github.shadowsocks.utils.Utils
 import net.glxn.qrgen.android.QRCode
 
 object QRCodeDialog {
@@ -50,8 +49,9 @@ final class QRCodeDialog extends DialogFragment {
   override def onCreateView(inflater: LayoutInflater, container: ViewGroup, savedInstanceState: Bundle): View = {
     val image = new ImageView(getActivity)
     image.setLayoutParams(new LinearLayout.LayoutParams(-1, -1))
+    val size = getResources.getDimensionPixelSize(R.dimen.qr_code_size)
     val qrcode = QRCode.from(url)
-      .withSize(Utils.dpToPx(getActivity, 250), Utils.dpToPx(getActivity, 250))
+      .withSize(size, size)
       .asInstanceOf[QRCode].bitmap()
     image.setImageBitmap(qrcode)
     image
diff --git a/mobile/src/main/scala/com/github/shadowsocks/utils/Utils.scala b/mobile/src/main/scala/com/github/shadowsocks/utils/Utils.scala
index 4937adfd..20a9e14c 100644
--- a/mobile/src/main/scala/com/github/shadowsocks/utils/Utils.scala
+++ b/mobile/src/main/scala/com/github/shadowsocks/utils/Utils.scala
@@ -56,8 +56,6 @@ object Utils {
     new String(Base64.encode(mdg.digest, 0))
   }
 
-  def dpToPx(context: Context, dp: Int): Int = Math.round(dp * context.getResources.getDisplayMetrics.density)
-
   /*
      * round or floor depending on whether you are using offsets(floor) or
      * widths(round)