diff --git a/app/(tabs)/(budget)/addCategory.tsx b/app/(tabs)/(budget)/addCategory.tsx
index a6c53b6..eced44a 100644
--- a/app/(tabs)/(budget)/addCategory.tsx
+++ b/app/(tabs)/(budget)/addCategory.tsx
@@ -5,6 +5,7 @@ import { SafeAreaView } from 'react-native-safe-area-context';
 import { AutoDecimalInput, CustomColorPicker, NavigationButton, TypeSelectorSwitch } from "../../../components";
 import { addCategory } from "../../../services/database";
 import { useTheme } from "../../contexts/ThemeContext";
+import { CategoryType } from "../../../services/database";
 
 export default function Page() {
     const {colors} = useTheme();
@@ -13,7 +14,9 @@ export default function Page() {
 
     const [categoryName, setCategoryName] = useState<string>("");
     const [categoryColor, setCategoryColor] = useState<string>('#' + Math.floor(Math.random()*16777215).toString(16));
-    const [selectedType, setSelectedType] = useState<string>("expense");
+
+    const [selectedType, setSelectedType] = useState<CategoryType>(CategoryType.EXPENSE);
+
     const [amount, setAmount] = useState(0);
 
     return (
@@ -35,7 +38,7 @@ export default function Page() {
 
                 <TypeSelectorSwitch 
                 currentSelected={selectedType}
-                handleButtonPress={(type) => {
+                handleButtonPress={(type: CategoryType) => {
                     setSelectedType(type);
                 }}
                 />
diff --git a/components/budget/typeSelectorSwitch.tsx b/components/budget/typeSelectorSwitch.tsx
index dc6231b..a4edf58 100644
--- a/components/budget/typeSelectorSwitch.tsx
+++ b/components/budget/typeSelectorSwitch.tsx
@@ -1,10 +1,11 @@
 
 import { StyleSheet, Text, TouchableOpacity, View } from "react-native";
 import { useTheme } from "../../app/contexts/ThemeContext";
+import { CategoryType } from "../../services/database";
 
 export type TypeSelectorSwitchProperties = {
-    handleButtonPress: (type: string) => void,
-    currentSelected: string,
+    handleButtonPress: (type: CategoryType) => void,
+    currentSelected: CategoryType,
 }
 
 const TypeSelectorSwitch = (properties: TypeSelectorSwitchProperties) => {
@@ -14,17 +15,17 @@ const TypeSelectorSwitch = (properties: TypeSelectorSwitchProperties) => {
         <View style={styles.containerStyle}>
             <TouchableOpacity 
             onPress={() => {
-                properties.handleButtonPress("expense");
+                properties.handleButtonPress(CategoryType.EXPENSE);
             }}
-            style={[styles.touchableOpacityStyle, properties.currentSelected == "expense" ? {backgroundColor: colors.accentColor} : {backgroundColor: colors.elementDefaultColor}]
+            style={[styles.touchableOpacityStyle, properties.currentSelected == CategoryType.EXPENSE ? {backgroundColor: colors.accentColor} : {backgroundColor: colors.elementDefaultColor}]
             }>
                 <Text style={[styles.textStyle, {color: colors.primaryText}]}>Expenses</Text>
             </TouchableOpacity>
             <TouchableOpacity 
-            onPress={() => {
-                properties.handleButtonPress("saving");
+                onPress={() => {
+                    properties.handleButtonPress(CategoryType.SAVING);
             }}
-            style={[styles.touchableOpacityStyle, properties.currentSelected == "saving" ? {backgroundColor: colors.accentColor} : {backgroundColor: colors.elementDefaultColor}]
+            style={[styles.touchableOpacityStyle, properties.currentSelected == CategoryType.SAVING ? {backgroundColor: colors.accentColor} : {backgroundColor: colors.elementDefaultColor}]
             }>
                 <Text style={[styles.textStyle, {color: colors.primaryText}]}>Savings</Text>
             </TouchableOpacity>
diff --git a/components/stats/BudgetOverview.tsx b/components/stats/BudgetOverview.tsx
index 05e89c4..8cc5c6c 100644
--- a/components/stats/BudgetOverview.tsx
+++ b/components/stats/BudgetOverview.tsx
@@ -2,6 +2,7 @@ import React, { useState, useEffect } from 'react';
 import { View, Text, StyleSheet } from 'react-native';
 import { useTheme } from '../../app/contexts/ThemeContext';
 import useFetch from '../../hooks/useFetch';
+import { CategoryType } from '../../services/database';
 
 const BudgetOverview = () => {
     const { colors } = useTheme();
@@ -9,12 +10,12 @@ const BudgetOverview = () => {
     const [budget, setBudget] = useState(0);
 
     const spentQuery = {
-        sql: "SELECT SUM(e.amount) as total FROM expense e LEFT JOIN category c ON e.category_guid = c.guid WHERE c.type = 'budget'",
+        sql: `SELECT SUM(e.amount) as total FROM expense e LEFT JOIN category c ON e.category_guid = c.guid WHERE c.type = '${CategoryType.EXPENSE.toString()}'`,
         args: []
     };    
 
     const budgetQuery = {
-        sql: "SELECT SUM(allocated_amount) as total FROM category WHERE type = 'budget'",
+        sql: `SELECT SUM(allocated_amount) as total FROM category WHERE type = '${CategoryType.EXPENSE.toString()}'`,
         args: []
     };
 
diff --git a/components/stats/BudgetRemaining.tsx b/components/stats/BudgetRemaining.tsx
index 37aa555..d5209fd 100644
--- a/components/stats/BudgetRemaining.tsx
+++ b/components/stats/BudgetRemaining.tsx
@@ -2,6 +2,7 @@ import React, { useState, useEffect } from 'react';
 import { Text, StyleSheet } from 'react-native';
 import { useTheme } from '../../app/contexts/ThemeContext';
 import useFetch from '../../hooks/useFetch';
+import { CategoryType } from '../../services/database';
 
 const styles = StyleSheet.create({
     text: {
@@ -23,7 +24,7 @@ const BudgetRemaining = () => {
     };
 
     const budgetQuery = {
-        sql: "SELECT SUM(allocated_amount) as total FROM category WHERE type = 'budget'",
+        sql: `SELECT SUM(allocated_amount) as total FROM category WHERE type = '${CategoryType.EXPENSE.toString()}'`,
         args: []
     };
 
diff --git a/components/stats/SavingsOverview.tsx b/components/stats/SavingsOverview.tsx
index a79234a..5162e75 100644
--- a/components/stats/SavingsOverview.tsx
+++ b/components/stats/SavingsOverview.tsx
@@ -2,6 +2,7 @@ import React, { useState, useEffect } from 'react';
 import { View, Text, StyleSheet } from 'react-native';
 import { useTheme } from '../../app/contexts/ThemeContext';
 import useFetch from '../../hooks/useFetch';
+import { CategoryType } from '../../services/database';
 
 const SavingsOverview = () => {
     const { colors } = useTheme();
@@ -9,12 +10,12 @@ const SavingsOverview = () => {
     const [goal, setGoal] = useState(0);
 
     const savedQuery = {
-        sql: "SELECT SUM(e.amount) as total FROM expense e LEFT JOIN category c ON e.category_guid = c.guid WHERE c.type = 'savings'",
+        sql: `SELECT SUM(e.amount) as total FROM expense e LEFT JOIN category c ON e.category_guid = c.guid WHERE c.type = '${CategoryType.SAVING.toString()}'`,
         args: []
     };  
 
     const goalQuery = {
-        sql: "SELECT SUM(allocated_amount) as total FROM category WHERE type = 'budget'",
+        sql: `SELECT SUM(allocated_amount) as total FROM category WHERE type = '${CategoryType.SAVING.toString()}'`,
         args: []
     };
 
diff --git a/services/database.ts b/services/database.ts
index 370108d..029131d 100644
--- a/services/database.ts
+++ b/services/database.ts
@@ -17,7 +17,7 @@ export const initDatabase = async () => {
     try {
         await db.transactionAsync(async (tx: SQLite.SQLTransactionAsync) => {
             await tx.executeSqlAsync(
-                "CREATE TABLE IF NOT EXISTS category (guid VARCHAR(36) PRIMARY KEY, name TEXT, color TEXT, type TEXT, allocated_amount DOUBLE);"
+                "CREATE TABLE IF NOT EXISTS category (guid VARCHAR(36) PRIMARY KEY, name TEXT, color TEXT, type string, allocated_amount DOUBLE);"
             );
             await tx.executeSqlAsync(
                 "CREATE TABLE IF NOT EXISTS expense (guid VARCHAR(36) PRIMARY KEY, name TEXT, category_guid VARCHAR(36), datetime DATETIME, amount DOUBLE, FOREIGN KEY (category_guid) REFERENCES category(guid));"