fix(a11y): enforce 44pt minimum tap targets on back buttons and touchables

src/components/PendingProofsBanner.tsx

@@ -53,6 +53,9 @@ export default function PendingProofsBanner({
           paddingVertical: spacing.sm,
           borderRadius: 10,
           backgroundColor: '#000',
+          minHeight: 44,
+          justifyContent: 'center',
+          alignItems: 'center',
           opacity: canRetry ? 1 : 0.6,
         }}
       >

src/components/PublicKeyDisplay.tsx

@@ -46,7 +46,7 @@ export default function PublicKeyDisplay({
         accessibilityRole="button"
         accessibilityLabel={`Wallet address ${publicKey}`}
         accessibilityHint="Double tap to toggle full address"
-        style={{ flexShrink: 1 }}
+        style={{ flexShrink: 1, minHeight: 44, justifyContent: 'center' }}
       >
         <Text
           style={[{ color: colors.textSecondary, fontSize: 12 }, textStyle]}
@@ -60,7 +60,14 @@ export default function PublicKeyDisplay({
         onPress={handleCopy}
         accessibilityRole="button"
         accessibilityLabel="Copy wallet address"
-        style={{ marginLeft: spacing.xs, padding: spacing.xs }}
+        style={{
+          marginLeft: spacing.xs,
+          padding: spacing.sm,
+          minWidth: 44,
+          minHeight: 44,
+          alignItems: 'center',
+          justifyContent: 'center',
+        }}
       >
         <Text style={{ fontSize: 14 }}>{copied ? '✅' : '📋'}</Text>
       </TouchableOpacity>

src/components/TransactionHistory.tsx

@@ -82,16 +82,18 @@ export default function TransactionHistory({
     return (
       <View style={{ marginTop: spacing.xl, alignItems: 'center' }}>
         <Text style={{ color: colors.error, fontSize: 13 }}>{error}</Text>
-        <TouchableOpacity onPress={() => void loadPayments()}>
-          <Text
-            style={{
-              color: colors.primary,
-              fontSize: 13,
-              marginTop: spacing.xs,
-            }}
-          >
-            Retry
-          </Text>
+        <TouchableOpacity
+          onPress={() => void loadPayments()}
+          accessibilityRole="button"
+          style={{
+            marginTop: spacing.xs,
+            paddingVertical: spacing.sm,
+            paddingHorizontal: spacing.md,
+            minHeight: 44,
+            justifyContent: 'center',
+          }}
+        >
+          <Text style={{ color: colors.primary, fontSize: 13 }}>Retry</Text>
         </TouchableOpacity>
       </View>
     );

src/screens/EditProfileScreen.tsx

@@ -72,7 +72,17 @@ export default function EditProfileScreen() {
         >
           <TouchableOpacity
             onPress={() => navigation.goBack()}
-            style={{ marginBottom: spacing.md }}
+            accessibilityRole="button"
+            accessibilityLabel="Cancel"
+            style={{
+              alignSelf: 'flex-start',
+              paddingVertical: spacing.sm,
+              paddingHorizontal: spacing.md,
+              marginLeft: -spacing.md,
+              marginBottom: spacing.md,
+              minHeight: 44,
+              justifyContent: 'center',
+            }}
           >
             <Text style={{ color: colors.primary, fontSize: 16 }}>Cancel</Text>
           </TouchableOpacity>

src/screens/MapScreen.tsx

@@ -394,6 +394,9 @@ const styles = StyleSheet.create({
   },
   retryBtn: {
     marginLeft: spacing.sm,
+    paddingHorizontal: spacing.sm,
+    minHeight: 44,
+    justifyContent: 'center',
   },
   retryText: {
     color: colors.primary,
@@ -424,6 +427,8 @@ const styles = StyleSheet.create({
     paddingHorizontal: spacing.md,
     paddingVertical: spacing.xs,
     borderRadius: 18,
+    minHeight: 44,
+    justifyContent: 'center',
   },
   radiusOptActive: {
     backgroundColor: colors.primary,

src/screens/SendTokensScreen.tsx

@@ -154,7 +154,19 @@ export default function SendTokensScreen() {
       behavior={Platform.OS === 'ios' ? 'padding' : undefined}
     >
       <View style={{ padding: spacing.lg, paddingTop: spacing.xl }}>
-        <TouchableOpacity onPress={() => navigation.goBack()}>
+        <TouchableOpacity
+          onPress={() => navigation.goBack()}
+          accessibilityRole="button"
+          accessibilityLabel="Cancel"
+          style={{
+            alignSelf: 'flex-start',
+            paddingVertical: spacing.sm,
+            paddingHorizontal: spacing.md,
+            marginLeft: -spacing.md,
+            minHeight: 44,
+            justifyContent: 'center',
+          }}
+        >
           <Text style={{ color: colors.primary, fontSize: 16 }}>Cancel</Text>
         </TouchableOpacity>
         <Text

src/screens/SubmitProofScreen.tsx

@@ -200,8 +200,22 @@ export default function SubmitProofScreen() {
   return (
     <View style={{ flex: 1, backgroundColor: colors.background }}>
       <View style={{ padding: spacing.lg, paddingTop: spacing.xl }}>
-        <TouchableOpacity onPress={() => navigation.goBack()}>
-          <Text style={{ color: colors.primary, fontSize: 16 }}>Back</Text>
+        <TouchableOpacity
+          onPress={() => navigation.goBack()}
+          accessibilityRole="button"
+          accessibilityLabel="Back"
+          style={{
+            alignSelf: 'flex-start',
+            paddingVertical: spacing.sm,
+            paddingHorizontal: spacing.md,
+            marginLeft: -spacing.md,
+            minHeight: 44,
+            justifyContent: 'center',
+          }}
+        >
+          <Text style={{ color: colors.primary, fontSize: 16 }}>
+            {'\u2190'} Back
+          </Text>
         </TouchableOpacity>
         <Text
           style={{
@@ -253,7 +267,14 @@ export default function SubmitProofScreen() {
             {hasPermission === false && (
               <TouchableOpacity
                 onPress={() => void requestPermission()}
-                style={{ marginTop: spacing.md, padding: spacing.sm }}
+                accessibilityRole="button"
+                style={{
+                  marginTop: spacing.md,
+                  paddingVertical: spacing.sm,
+                  paddingHorizontal: spacing.md,
+                  minHeight: 44,
+                  justifyContent: 'center',
+                }}
               >
                 <Text style={{ color: colors.primary }}>Grant Permission</Text>
               </TouchableOpacity>

src/screens/TaskDetailScreen.tsx

@@ -65,7 +65,14 @@ export default function TaskDetailScreen() {
         <Text style={{ color: colors.error }}>{error || 'Task not found'}</Text>
         <TouchableOpacity
           onPress={() => void loadTask()}
-          style={{ marginTop: spacing.md }}
+          accessibilityRole="button"
+          style={{
+            marginTop: spacing.md,
+            paddingVertical: spacing.sm,
+            paddingHorizontal: spacing.md,
+            minHeight: 44,
+            justifyContent: 'center',
+          }}
         >
           <Text style={{ color: colors.primary }}>Try Again</Text>
         </TouchableOpacity>
@@ -83,7 +90,18 @@ export default function TaskDetailScreen() {
       <View style={{ padding: spacing.lg }}>
         <TouchableOpacity
           onPress={() => navigation.goBack()}
-          style={{ marginBottom: spacing.md, marginTop: spacing.xl }}
+          accessibilityRole="button"
+          accessibilityLabel="Back"
+          style={{
+            alignSelf: 'flex-start',
+            paddingVertical: spacing.sm,
+            paddingHorizontal: spacing.md,
+            marginLeft: -spacing.md,
+            marginTop: spacing.xl,
+            marginBottom: spacing.md,
+            minHeight: 44,
+            justifyContent: 'center',
+          }}
         >
           <Text style={{ color: colors.primary, fontSize: 16 }}>
             {'\u2190'} Back

src/screens/TaskListScreen.tsx

@@ -124,7 +124,14 @@ export default function TaskListScreen() {
         <Text style={{ color: colors.error }}>{error}</Text>
         <TouchableOpacity
           onPress={() => void refresh()}
-          style={{ marginTop: spacing.md }}
+          accessibilityRole="button"
+          style={{
+            marginTop: spacing.md,
+            paddingVertical: spacing.sm,
+            paddingHorizontal: spacing.md,
+            minHeight: 44,
+            justifyContent: 'center',
+          }}
         >
           <Text style={{ color: colors.primary }}>Retry</Text>
         </TouchableOpacity>
@@ -168,6 +175,7 @@ export default function TaskListScreen() {
               paddingVertical: spacing.sm,
               borderRadius: 20,
               marginRight: spacing.sm,
+              minHeight: 44,
               backgroundColor:
                 activeType === t.key ? colors.primary : colors.surface,
               borderWidth: 1,
@@ -206,6 +214,8 @@ export default function TaskListScreen() {
               paddingVertical: spacing.xs,
               borderRadius: 16,
               marginRight: spacing.sm,
+              minHeight: 44,
+              justifyContent: 'center',
               backgroundColor:
                 statusFilter === s.key ? colors.primary : colors.surface,
               borderWidth: 1,
@@ -263,6 +273,8 @@ export default function TaskListScreen() {
               paddingVertical: spacing.xs,
               borderRadius: 16,
               marginRight: spacing.sm,
+              minHeight: 44,
+              justifyContent: 'center',
               backgroundColor:
                 sortMode === opt.key ? colors.primary : colors.surface,
               borderWidth: 1,
@@ -296,6 +308,8 @@ export default function TaskListScreen() {
                   paddingVertical: spacing.xs,
                   borderRadius: 12,
                   marginLeft: spacing.xs,
+                  minHeight: 44,
+                  justifyContent: 'center',
                   backgroundColor:
                     radiusKm === km ? colors.primaryDark : colors.surface,
                 }}