diff --git a/CHANGELOG.md b/CHANGELOG.md
index 97568cd5..b897768d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,11 @@ Read `release_notes.md` for commit level details.
 ### Bug fixes
 
 ### Deprecations
+- Stop converting snake cases to camel case for symbols in capabilities
+    - Please define camel/snake cases in capabilities as-is for the WebDriver capabilities
+- Stop implicit symbolizing capabilities
+    - Historically ruby_lib/ruby_lib_core symbolized capabilities keys from string internally.
+    - `Appium.symbolize_keys` to build symbolized capabilities if issues occurred by this change.
 
 ## [8.0.2] - 2024-04-26
 
diff --git a/lib/appium_lib_core.rb b/lib/appium_lib_core.rb
index 12b0ccb0..8d1a1cfa 100644
--- a/lib/appium_lib_core.rb
+++ b/lib/appium_lib_core.rb
@@ -22,15 +22,17 @@
 require_relative 'appium_lib_core/support/event_firing_bridge'
 
 module Appium
-  # @private
-  #
   # convert the top level keys to symbols.
   #
   # @param [Hash] hash Hash value to make symbolise
+  #
+  # @example
+  # opts = Appium.symbolize_keys(opts)
+  #
   def self.symbolize_keys(hash, nested: false, enable_deprecation_msg: true)
     # FIXME: As https://github.com/appium/ruby_lib/issues/945, we must remove this implicit string to symbol.
     # But appium_lib_core's some capability handling expect to be symbol, so we should test to remove
-    # the mehotds which expect the symbol first.
+    # the methods which expect the symbol first.
     raise ::Appium::Core::Error::ArgumentError, 'symbolize_keys requires a hash' unless hash.is_a? Hash
 
     hash.each_with_object({}) do |pair, acc|
diff --git a/lib/appium_lib_core/common/base/capabilities.rb b/lib/appium_lib_core/common/base/capabilities.rb
index caaf5c74..4a6ba521 100644
--- a/lib/appium_lib_core/common/base/capabilities.rb
+++ b/lib/appium_lib_core/common/base/capabilities.rb
@@ -23,6 +23,20 @@ class Capabilities < ::Selenium::WebDriver::Remote::Capabilities
         # Appium's capabilities could change by depending on Appium versions. So it does not have
         # standard options like chrome and firefox etc. So, the implementation should differ from
         # other browsers. But here should inherit `Options` to follow Selenium.
+
+        # Method override
+        # FIXME: when we drop "symbolize_keys", this can be removed.
+        def convert_key(key)
+          case key
+          when String
+            key.to_s
+          when Symbol
+            # here do not convert to camel case
+            key.to_s
+          else
+            raise TypeError, "expected String or Symbol, got #{key.inspect}:#{key.class}"
+          end
+        end
       end
     end
   end
diff --git a/lib/appium_lib_core/driver.rb b/lib/appium_lib_core/driver.rb
index 5e6c9e22..ceb5eba6 100644
--- a/lib/appium_lib_core/driver.rb
+++ b/lib/appium_lib_core/driver.rb
@@ -338,12 +338,6 @@ def initialize
       def setup_for_new_session(opts = {})
         @custom_url = opts.delete :url # to set the custom url as :url
 
-        # TODO: Remove when we implement Options
-        # The symbolize_keys is to keep compatiility for the legacy code, which allows capabilities to give 'string' as the key.
-        # The toplevel `caps`, `capabilities` and `appium_lib` are expected to be symbol.
-        # FIXME: First, please try to remove `nested: true` to `nested: false`.
-        opts = Appium.symbolize_keys(opts, nested: true)
-
         @caps = get_caps(opts)
 
         set_appium_lib_specific_values(get_appium_lib_opts(opts))
@@ -635,22 +629,27 @@ def get_appium_lib_opts(opts)
         opts[:appium_lib] || {}
       end
 
+      # @private
+      def get_app
+        @caps[:app] || @caps['app']
+      end
+
       # @private
       # Path to the .apk, .app or .app.zip.
       # The path can be local, HTTP/S, Windows Share and other path like 'sauce-storage:'.
       # Use @caps[:app] without modifications if the path isn't HTTP/S or local path.
       def set_app_path
         # FIXME: maybe `:app` should check `app` as well.
-        return unless @caps && @caps[:app] && !@caps[:app].empty?
-        return if @caps[:app] =~ URI::DEFAULT_PARSER.make_regexp
-
-        app_path = File.expand_path(@caps[:app])
-        @caps[:app] = if File.exist? app_path
-                        app_path
-                      else
-                        ::Appium::Logger.warn("Use #{@caps[:app]} directly since #{app_path} does not exist.")
-                        @caps[:app]
-                      end
+        return unless @caps && get_app && !get_app.empty?
+        return if get_app =~ URI::DEFAULT_PARSER.make_regexp
+
+        app_path = File.expand_path(get_app)
+        @caps['app'] = if File.exist? app_path
+                         app_path
+                       else
+                         ::Appium::Logger.warn("Use #{get_app} directly since #{app_path} does not exist.")
+                         get_app
+                       end
       end
 
       # @private
@@ -676,7 +675,6 @@ def set_appium_lib_specific_values(appium_lib_opts)
       # @private
       def set_appium_device
         # https://code.google.com/p/selenium/source/browse/spec-draft.md?repo=mobile
-        # TODO: check if the Appium.symbolize_keys(opts, nested: false) enoug with this
         @device = @caps[:platformName] || @caps['platformName']
         return @device unless @device
 
@@ -685,7 +683,6 @@ def set_appium_device
 
       # @private
       def set_automation_name
-        # TODO: check if the Appium.symbolize_keys(opts, nested: false) enoug with this
         candidate = @caps[:automationName] || @caps['automationName']
         @automation_name = candidate if candidate
         @automation_name = convert_downcase @automation_name if @automation_name
diff --git a/test/unit/common_test.rb b/test/unit/common_test.rb
index 035b838d..135c3725 100644
--- a/test/unit/common_test.rb
+++ b/test/unit/common_test.rb
@@ -158,10 +158,10 @@ def test_add_appium_prefix_already_have_appium_prefix
           'platformVersion' => '11.4',
           'deviceName' => 'iPhone Simulator',
           'useNewWDA' => true,
-          'someCapability1' => 'some_capability1',
+          'some_capability1' => 'some_capability1',
           'someCapability2' => '',
           'some_capability3' => 'string_shold_keep',
-          'some_capability4' => { 'nested_key1' => 1, 'nestedKey2' => 2 }
+          'some_capability4' => { 'nested_key1' => 1, 'nested_key2' => 2 }
         }
         assert_equal expected, base_caps.as_json
 
@@ -196,7 +196,7 @@ def test_add_appium_prefix_already_have_appium_prefix
           'appium:some_capability3' => 'string_shold_keep',
           'appium:some_capability4' => {
             'nested_key1' => 1,
-            'nestedKey2' => 2
+            'nested_key2' => 2
           }
         }
         # for testing
diff --git a/test/unit/driver_test.rb b/test/unit/driver_test.rb
index 6093eeac..ad5eec0b 100644
--- a/test/unit/driver_test.rb
+++ b/test/unit/driver_test.rb
@@ -49,7 +49,7 @@ def test_with_caps_and_appium_lib
       opts = { 'caps' => { 'automationName': 'xcuitest' }, appium_lib: {} }
       driver = ExampleDriver.new(opts)
       refute_nil driver
-      assert_equal driver.core.caps[:automationName], 'xcuitest'
+      assert_equal driver.core.caps[:automationName], nil
     end
 
     def test_verify_appium_core_base_capabilities_create_capabilities
@@ -67,7 +67,7 @@ def test_verify_appium_core_base_capabilities_create_capabilities
       assert_equal 'test/functional/app/UICatalog.app.zip', caps_with_json['app']
       assert_equal 'XCUITest', caps_with_json['automationName']
       assert_equal 'iPhone Simulator', caps_with_json['deviceName']
-      assert_equal 'some_capability1', caps_with_json['someCapability1']
+      assert_equal 'some_capability1', caps_with_json['some_capability1']
       assert_equal 'someCapability2', caps_with_json['someCapability2']
 
       assert_equal 'ios', caps[:platformName]