API for apps to register for push notifications

db/migrate/20170129000348_create_devices.rb

@@ -0,0 +1,13 @@
+class CreateDevices < ActiveRecord::Migration[5.0]
+  def change
+    create_table :devices do |t|
+      t.integer :account_id, null: false
+      t.string :registration_id, null: false, default: ''
+
+      t.timestamps
+    end
+
+    add_index :devices, :registration_id
+    add_index :devices, :account_id
+  end
+end