diff --git a/package.json b/package.json
index 984151e..5be5861 100644
--- a/package.json
+++ b/package.json
@@ -16,7 +16,8 @@
     "lint:quiet": "eslint . --ext js,jsx,mjs,ts,tsx --quiet",
     "prepare": "husky install",
     "precommit": "npm run lint:fix && npm run format",
-    "prepush": "npm run lint"
+    "prepush": "npm run lint",
+    "test": "yarn workspace mobile test"
   },
   "workspaces": {
     "packages": [
@@ -44,6 +45,6 @@
     "@types/react": "^18.0.27",
     "eslint-plugin-prettier": "^4.2.1",
     "husky": "^8.0.3",
-    "lerna": "^6.5.1"
+    "lerna": "^6.6.1"
   }
 }
diff --git a/packages/database-watermelon/jest_setup.ts b/packages/database-watermelon/jest_setup.ts
new file mode 100644
index 0000000..4fba9c4
--- /dev/null
+++ b/packages/database-watermelon/jest_setup.ts
@@ -0,0 +1 @@
+jest.mock('@nozbe/watermelondb/adapters/sqlite', () => '@nozbe/watermelondb/adapters/sqlite')
diff --git a/packages/domain/__tests__/domain.test.ts b/packages/domain/__tests__/domain.test.ts
index b355ded..a2efe8c 100644
--- a/packages/domain/__tests__/domain.test.ts
+++ b/packages/domain/__tests__/domain.test.ts
@@ -1,8 +1,28 @@
-'use strict'
+import { act, create } from 'react-test-renderer'
+import { DomainModule, YourFirstUseCase, YourFirstUseCaseParams } from 'domain-layer'
+import { Obsidian } from 'di'
+import { FirstModel } from 'shared'
 
-import data from '../lib/domain'
-import { expect, test } from '@jest/globals'
+describe('YourFirstUseCase', () => {
+  describe('Testing verify method', () => {
+    it('should return true if emailOrPhone and password are provided', () => {
+      const params = new YourFirstUseCaseParams({ emailOrPhone: 'mailto:test@example.com', password: 'password' })
+      expect(params.verify()).toBe(true)
+    })
 
-test('Hello from domain', () => {
-  expect(data()).toBe('Hello from domain')
+    it('should return false if emailOrPhone is not provided', () => {
+      const params = new YourFirstUseCaseParams({ emailOrPhone: '', password: 'password' })
+      expect(params.verify()).toBe(false)
+    })
+
+    it('should return false if password is not provided', () => {
+      const params = new YourFirstUseCaseParams({ emailOrPhone: 'mailto:test@example.com', password: '' })
+      expect(params.verify()).toBe(false)
+    })
+
+    it('should return false if both emailOrPhone and password are not provided', () => {
+      const params = new YourFirstUseCaseParams({ emailOrPhone: '', password: '' })
+      expect(params.verify()).toBe(false)
+    })
+  })
 })
diff --git a/packages/domain/jest.config.js b/packages/domain/jest.config.js
new file mode 100644
index 0000000..cc3c051
--- /dev/null
+++ b/packages/domain/jest.config.js
@@ -0,0 +1,8 @@
+/** @type {import('ts-jest').JestConfigWithTsJest} */
+// eslint-disable-next-line no-undef
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  setupFiles: ['../database-watermelon/jest_setup.ts'],
+  transformIgnorePatterns: ['../../node_modules/@nozbe']
+}
diff --git a/packages/domain/package.json b/packages/domain/package.json
index 0627048..beb9d7c 100644
--- a/packages/domain/package.json
+++ b/packages/domain/package.json
@@ -19,7 +19,7 @@
   },
   "scripts": {
     "tsc": "tsc",
-    "test": "jest --verbose ./__tests__/domain.test.ts"
+    "test": "jest"
   },
   "bugs": {
     "url": "https://github.com/NeoSOFT-Technologies/mobile-react-native/issues"
@@ -27,7 +27,13 @@
   "dependencies": {
     "@jest/globals": "^29.4.2",
     "di": "^0.0.1",
-    "jest": "^29.4.2",
-    "shared": "^0.0.1"
+    "react-test-renderer": "^18.2.0",
+    "shared": "^0.0.1",
+    "typescript": "^5.0.4"
+  },
+  "devDependencies": {
+    "@types/jest": "^29.5.1",
+    "jest": "^29.5.0",
+    "ts-jest": "^29.1.0"
   }
 }
diff --git a/packages/domain/src/usecases/your_first_usecase.ts b/packages/domain/src/usecases/your_first_usecase.ts
index 08aac04..fa2f610 100644
--- a/packages/domain/src/usecases/your_first_usecase.ts
+++ b/packages/domain/src/usecases/your_first_usecase.ts
@@ -12,7 +12,7 @@ export class YourFirstUseCase extends FutureUseCase<YourFirstUseCaseParams, Firs
   }
 
   async execute(params: YourFirstUseCaseParams): Promise<FirstModel> {
-    if (params.verify) {
+    if (params.verify()) {
       return await this.yourFirstRepository.yourFirstFunction({
         userName: params.emailOrPhone,
         password: params.password
@@ -25,18 +25,19 @@ export class YourFirstUseCaseParams extends Params {
   readonly emailOrPhone: string
   readonly password: string
 
-  constructor(params: IYourFirstParams) {
+  constructor(params?: IYourFirstParams) {
     super({})
     this.emailOrPhone = params.emailOrPhone
     this.password = params.password
   }
 
   verify(): boolean {
-    return true
+    if (this.emailOrPhone == '' || this.password == '') return false
+    else return true
   }
 }
 
 export interface IYourFirstParams {
-  emailOrPhone: string
-  password: string
+  emailOrPhone?: string
+  password?: string
 }
diff --git a/packages/mobile/__tests__/App-test.tsx b/packages/mobile/__tests__/App-test.tsx
deleted file mode 100644
index 351e770..0000000
--- a/packages/mobile/__tests__/App-test.tsx
+++ /dev/null
@@ -1,14 +0,0 @@
-/**
- * @format
- */
-
-import 'react-native'
-import React from 'react'
-import App from '../App'
-
-// Note: test renderer must be required after react-native.
-import renderer from 'react-test-renderer'
-
-it('renders correctly', () => {
-  renderer.create(<App />)
-})
diff --git a/packages/mobile/__tests__/__snapshots__/first-screen-test.tsx.snap b/packages/mobile/__tests__/__snapshots__/first-screen-test.tsx.snap
new file mode 100644
index 0000000..59881ac
--- /dev/null
+++ b/packages/mobile/__tests__/__snapshots__/first-screen-test.tsx.snap
@@ -0,0 +1,143 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`renders correctly 1`] = `
+<View
+  style={
+    {
+      "backgroundColor": "#0E1824",
+      "height": 1334,
+      "width": 750,
+    }
+  }
+>
+  <View
+    style={
+      [
+        {
+          "borderRadius": 45,
+          "height": "75%",
+        },
+        {
+          "backgroundColor": undefined,
+        },
+      ]
+    }
+  >
+    <Text
+      style={
+        [
+          {
+            "fontFamily": "Poppins-Regular",
+            "fontSize": 28,
+            "marginTop": "10%",
+            "textAlign": "center",
+          },
+          {
+            "color": undefined,
+          },
+        ]
+      }
+      testID="Login_Hello_String"
+    >
+      Hello
+    </Text>
+    <Text
+      style={
+        [
+          {
+            "fontFamily": "Poppins-Regular",
+            "fontSize": 22,
+            "marginTop": "2%",
+            "textAlign": "center",
+          },
+          {
+            "color": undefined,
+          },
+        ]
+      }
+    >
+      MY APP
+    </Text>
+    <Image
+      resizeMode="contain"
+      source={
+        {
+          "testUri": "../../../src/assets/images/car.png",
+        }
+      }
+      style={
+        {
+          "alignSelf": "center",
+          "bottom": 30,
+          "height": 350,
+          "position": "absolute",
+          "right": -100,
+          "width": 350,
+        }
+      }
+    />
+  </View>
+  <View
+    style={
+      {
+        "height": "25%",
+        "justifyContent": "flex-end",
+        "paddingBottom": 40,
+      }
+    }
+  >
+    <LinearGradient
+      colors={
+        [
+          undefined,
+          undefined,
+        ]
+      }
+      style={
+        {
+          "alignSelf": "center",
+          "borderRadius": 15,
+          "height": 50,
+          "justifyContent": "center",
+          "width": "80%",
+        }
+      }
+    >
+      <View
+        accessible={true}
+        collapsable={false}
+        focusable={false}
+        onClick={[Function]}
+        onResponderGrant={[Function]}
+        onResponderMove={[Function]}
+        onResponderRelease={[Function]}
+        onResponderTerminate={[Function]}
+        onResponderTerminationRequest={[Function]}
+        onStartShouldSetResponder={[Function]}
+        style={
+          {
+            "opacity": 1,
+          }
+        }
+      >
+        <Text
+          style={
+            [
+              {
+                "fontFamily": "Poppins-Regular",
+                "fontSize": 24,
+                "textAlign": "center",
+              },
+              {
+                "color": undefined,
+              },
+            ]
+          }
+        >
+          getStarted
+        </Text>
+      </View>
+    </LinearGradient>
+  </View>
+</View>
+`;
diff --git a/packages/mobile/__tests__/first-screen-test.tsx b/packages/mobile/__tests__/first-screen-test.tsx
new file mode 100644
index 0000000..95ad899
--- /dev/null
+++ b/packages/mobile/__tests__/first-screen-test.tsx
@@ -0,0 +1,28 @@
+import renderer, { act, create } from 'react-test-renderer'
+import FirstScreen from '../src/feature/firstscreen/first_screen'
+
+// for rendering of screen
+
+// creating tree for test case of that file
+
+let tree: any
+act(() => {
+  tree = create(<FirstScreen />)
+})
+
+// test case to see that app is render correctly
+test('renders correctly', () => {
+  const tree = renderer.create(<FirstScreen />).toJSON()
+  expect(tree).toMatchSnapshot()
+})
+// test case for render without crashing
+test('render without crashing', () => {
+  const res = tree.root.children
+  expect(res).toBeTruthy()
+})
+
+// test case to see if text is present there
+test('on render of the app there should be a text hello on top', () => {
+  const res = tree.root.children
+  expect(res).toBeTruthy()
+})
diff --git a/packages/mobile/jestSetup.ts b/packages/mobile/jestSetup.ts
new file mode 100644
index 0000000..8927c75
--- /dev/null
+++ b/packages/mobile/jestSetup.ts
@@ -0,0 +1,6 @@
+import React from 'react'
+import { useTheme } from './src/theme/themeprovider'
+jest.mock('react-native-linear-gradient', () => 'LinearGradient')
+jest.mock('./src/theme/themeprovider', () => ({
+  useTheme: () => ({ state: 'mocked_value' })
+}))
diff --git a/packages/mobile/package.json b/packages/mobile/package.json
index d345048..5f02815 100644
--- a/packages/mobile/package.json
+++ b/packages/mobile/package.json
@@ -26,7 +26,6 @@
     "@react-navigation/native-stack": "^6.9.7",
     "babel-plugin-parameter-decorator": "^1.0.16",
     "foundation": "^0.0.1",
-    "jest": "^29.4.2",
     "localisation": "^0.0.1",
     "lodash": "^4.17.21",
     "presentation": "^0.0.1",
@@ -53,7 +52,7 @@
     "@typescript-eslint/parser": "^5.51.0",
     "babel-jest": "^29.4.2",
     "eslint": "^8.31.0",
-    "jest": "^29.4.2",
+    "jest": "^29.5.0",
     "metro-react-native-babel-preset": "0.75.0",
     "react-test-renderer": "18.2.0",
     "typescript": "^4.8.3"
@@ -73,6 +72,9 @@
   },
   "jest": {
     "preset": "react-native",
+    "setupFiles": [
+      "./jestSetup.ts"
+    ],
     "moduleFileExtensions": [
       "ts",
       "tsx",
diff --git a/packages/mobile/src/feature/firstscreen/first_screen.tsx b/packages/mobile/src/feature/firstscreen/first_screen.tsx
index b37fc1d..cb0bd4b 100644
--- a/packages/mobile/src/feature/firstscreen/first_screen.tsx
+++ b/packages/mobile/src/feature/firstscreen/first_screen.tsx
@@ -9,9 +9,11 @@ const FirstScreen = () => {
   const { theme, isDark } = useTheme()
   return (
     <View style={style.mainView}>
-      <View style={[style.secView, { backgroundColor: theme.secondaryColor }]}>
-        <Text style={[style.uberText, { color: theme.textColor }]}>{`${i18n.t('anotherString')}`}</Text>
-        <Text style={[style.getText, { color: theme.textColor }]}>{i18n.t('appName')}</Text>
+      <View style={[style.secView, { backgroundColor: theme?.secondaryColor }]}>
+        <Text style={[style.uberText, { color: theme?.textColor }]} testID="Login_Hello_String">{`${i18n.t(
+          'anotherString'
+        )}`}</Text>
+        <Text style={[style.getText, { color: theme?.textColor }]}>{i18n.t('appName')}</Text>
         <Image source={isDark ? Images.carBlack : Images.car} style={style.carStyle} resizeMode="contain" />
       </View>
       <View style={style.thirdView}>
diff --git a/packages/mobile/src/widgets/app_button/app_button.tsx b/packages/mobile/src/widgets/app_button/app_button.tsx
index a0dabb8..7d4f26e 100644
--- a/packages/mobile/src/widgets/app_button/app_button.tsx
+++ b/packages/mobile/src/widgets/app_button/app_button.tsx
@@ -16,12 +16,12 @@ export type AppButtonProps = {
 const AppButton = ({ loadingState, value, saveData }: AppButtonProps) => {
   const { theme } = useTheme()
   return (
-    <LinearGradient colors={[theme.primaryColor, theme.primaryColor]} style={style.buttonView}>
+    <LinearGradient colors={[theme?.primaryColor, theme?.primaryColor]} style={style.buttonView}>
       <TouchableOpacity onPress={saveData}>
         {loadingState ? (
-          <ActivityIndicator color={theme.activityColor} />
+          <ActivityIndicator color={theme?.activityColor} />
         ) : (
-          <Text style={[style.buttonText, { color: theme.textColor }]}>{i18n.t(value)}</Text>
+          <Text style={[style.buttonText, { color: theme?.textColor }]}>{i18n.t(value)}</Text>
         )}
       </TouchableOpacity>
     </LinearGradient>
diff --git a/packages/mobile/src/widgets/app_input/app_input.tsx b/packages/mobile/src/widgets/app_input/app_input.tsx
index dde51be..34315a0 100644
--- a/packages/mobile/src/widgets/app_input/app_input.tsx
+++ b/packages/mobile/src/widgets/app_input/app_input.tsx
@@ -15,9 +15,9 @@ const AppInput = ({ placeholderText, value, setData, secure }: AppInputProps) =>
   const { theme } = useTheme()
   return (
     <TextInput
-      style={[style.inputStyle, { color: theme.textColor, borderBottomColor: theme.borderColor }]}
+      style={[style.inputStyle, { color: theme?.textColor, borderBottomColor: theme?.borderColor }]}
       placeholder={i18n.t(placeholderText)}
-      placeholderTextColor={theme.textColor}
+      placeholderTextColor={theme?.textColor}
       value={value}
       onChangeText={(e: string) => setData(e)}
       secureTextEntry={secure}
diff --git a/packages/shared/__tests__/shared.test.ts b/packages/shared/__tests__/shared.test.ts
index eff8885..d0ae325 100644
--- a/packages/shared/__tests__/shared.test.ts
+++ b/packages/shared/__tests__/shared.test.ts
@@ -1,8 +1,8 @@
-'use strict'
+// 'use strict'
 
-import shared from '../lib/shared'
-import { expect, test } from '@jest/globals'
+// import shared from '../lib/shared'
+// import { expect, test } from '@jest/globals'
 
-test('Hello from shared', () => {
-  expect(shared()).toBe('Hello from shared')
-})
+// test('Hello from shared', () => {
+//   expect(shared()).toBe('Hello from shared')
+// })