"""
Metadata optimization module for App Store Optimization.
Optimizes titles, descriptions, and keyword fields with platform-specific character limit validation.
"""
from typing import Dict, List, Any, Optional, Tuple
import re
class MetadataOptimizer:
"""Optimizes app store metadata for maximum discoverability and conversion."""
# Platform-specific character limits
CHAR_LIMITS = {
'apple': {
'title': 30,
'subtitle': 30,
'promotional_text': 170,
'description': 4000,
'keywords': 100,
'whats_new': 4000
},
'google': {
'title': 50,
'short_description': 80,
'full_description': 4000
}
}
def __init__(self, platform: str = 'apple'):
"""
Initialize metadata optimizer.
Args:
platform: 'apple' or 'google'
"""
if platform not in ['apple', 'google']:
raise ValueError("Platform must be 'apple' or 'google'")
self.platform = platform
self.limits = self.CHAR_LIMITS[platform]
def optimize_title(
self,
app_name: str,
target_keywords: List[str],
include_brand: bool = True
) -> Dict[str, Any]:
"""
Optimize app title with keyword integration.
Args:
app_name: Your app's brand name
target_keywords: List of keywords to potentially include
include_brand: Whether to include brand name
Returns:
Optimized title options with analysis
"""
max_length = self.limits['title']
title_options = []
# Option 1: Brand name only
if include_brand:
option1 = app_name[:max_length]
title_options.append({
'title': option1,
'length': len(option1),
'remaining_chars': max_length - len(option1),
'keywords_included': [],
'strategy': 'brand_only',
'pros': ['Maximum brand recognition', 'Clean and simple'],
'cons': ['No keyword targeting', 'Lower discoverability']
})
# Option 2: Brand + Primary Keyword
if target_keywords:
primary_keyword = target_keywords[0]
option2 = self._build_title_with_keywords(
app_name,
[primary_keyword],
max_length
)
if option2:
title_options.append({
'title': option2,
'length': len(option2),
'remaining_chars': max_length - len(option2),
'keywords_included': [primary_keyword],
'strategy': 'brand_plus_primary',
'pros': ['Targets main keyword', 'Maintains brand identity'],
'cons': ['Limited keyword coverage']
})
# Option 3: Brand + Multiple Keywords (if space allows)
if len(target_keywords) > 1:
option3 = self._build_title_with_keywords(
app_name,
target_keywords[:2],
max_length
)
if option3:
title_options.append({
'title': option3,
'length': len(option3),
'remaining_chars': max_length - len(option3),
'keywords_included': target_keywords[:2],
'strategy': 'brand_plus_multiple',
'pros': ['Multiple keyword targets', 'Better discoverability'],
'cons': ['May feel cluttered', 'Less brand focus']
})
# Option 4: Keyword-first approach (for new apps)
if target_keywords and not include_brand:
option4 = " ".join(target_keywords[:2])[:max_length]
title_options.append({
'title': option4,
'length': len(option4),
'remaining_chars': max_length - len(option4),
'keywords_included': target_keywords[:2],
'strategy': 'keyword_first',
'pros': ['Maximum SEO benefit', 'Clear functionality'],
'cons': ['No brand recognition', 'Generic appearance']
})
return {
'platform': self.platform,
'max_length': max_length,
'options': title_options,
'recommendation': self._recommend_title_option(title_options)
}
def optimize_description(
self,
app_info: Dict[str, Any],
target_keywords: List[str],
description_type: str = 'full'
) -> Dict[str, Any]:
"""
Optimize app description with keyword integration and conversion focus.
Args:
app_info: Dict with 'name', 'key_features', 'unique_value', 'target_audience'
target_keywords: List of keywords to integrate naturally
description_type: 'full', 'short' (Google), 'subtitle' (Apple)
Returns:
Optimized description with analysis
"""
if description_type == 'short' and self.platform == 'google':
return self._optimize_short_description(app_info, target_keywords)
elif description_type == 'subtitle' and self.platform == 'apple':
return self._optimize_subtitle(app_info, target_keywords)
else:
return self._optimize_full_description(app_info, target_keywords)
def optimize_keyword_field(
self,
target_keywords: List[str],
app_title: str = "",
app_description: str = ""
) -> Dict[str, Any]:
"""
Optimize Apple's 100-character keyword field.
Rules:
- No spaces between commas
- No plural forms if singular exists
- No duplicates
- Keywords in title/subtitle are already indexed
Args:
target_keywords: List of target keywords
app_title: Current app title (to avoid duplication)
app_description: Current description (to check coverage)
Returns:
Optimized keyword field (comma-separated, no spaces)
"""
if self.platform != 'apple':
return {'error': 'Keyword field optimization only applies to Apple App Store'}
max_length = self.limits['keywords']
# Extract words already in title (these don't need to be in keyword field)
title_words = set(app_title.lower().split()) if app_title else set()
# Process keywords
processed_keywords = []
for keyword in target_keywords:
keyword_lower = keyword.lower().strip()
# Skip if already in title
if keyword_lower in title_words:
continue
# Remove duplicates and process
words = keyword_lower.split()
for word in words:
if word not in processed_keywords and word not in title_words:
processed_keywords.append(word)
# Remove plurals if singular exists
deduplicated = self._remove_plural_duplicates(processed_keywords)
# Build keyword field within 100 character limit
keyword_field = self._build_keyword_field(deduplicated, max_length)
# Calculate keyword density in description
density = self._calculate_coverage(target_keywords, app_description)
return {
'keyword_field': keyword_field,
'length': len(keyword_field),
'remaining_chars': max_length - len(keyword_field),
'keywords_included': keyword_field.split(','),
'keywords_count': len(keyword_field.split(',')),
'keywords_excluded': [kw for kw in target_keywords if kw.lower() not in keyword_field],
'description_coverage': density,
'optimization_tips': [
'Keywords in title are auto-indexed - no need to repeat',
'Use singular forms only (Apple indexes plurals automatically)',
'No spaces between commas to maximize character usage',
'Update keyword field with each app update to test variations'
]
}
def validate_character_limits(
self,
metadata: Dict[str, str]
) -> Dict[str, Any]:
"""
Validate all metadata fields against platform character limits.
Args:
metadata: Dictionary of field_name: value
Returns:
Validation report with errors and warnings
"""
validation_results = {
'is_valid': True,
'errors': [],
'warnings': [],
'field_status': {}
}
for field_name, value in metadata.items():
if field_name not in self.limits:
validation_results['warnings'].append(
f"Unknown field '{field_name}' for {self.platform} platform"
)
continue
max_length = self.limits[field_name]
actual_length = len(value)
remaining = max_length - actual_length
field_status = {
'value': value,
'length': actual_length,
'limit': max_length,
'remaining': remaining,
'is_valid': actual_length <= max_length,
'usage_percentage': round((actual_length / max_length) * 100, 1)
}
validation_results['field_status'][field_name] = field_status
if actual_length > max_length:
validation_results['is_valid'] = False
validation_results['errors'].append(
f"'{field_name}' exceeds limit: {actual_length}/{max_length} chars"
)
elif remaining > max_length * 0.2: # More than 20% unused
validation_results['warnings'].append(
f"'{field_name}' under-utilizes space: {remaining} chars remaining"
)
return validation_results
def calculate_keyword_density(
self,
text: str,
target_keywords: List[str]
) -> Dict[str, Any]:
"""
Calculate keyword density in text.
Args:
text: Text to analyze
target_keywords: Keywords to check
Returns:
Density analysis
"""
text_lower = text.lower()
total_words = len(text_lower.split())
keyword_densities = {}
for keyword in target_keywords:
keyword_lower = keyword.lower()
count = text_lower.count(keyword_lower)
density = (count / total_words * 100) if total_words > 0 else 0
keyword_densities[keyword] = {
'occurrences': count,
'density_percentage': round(density, 2),
'status': self._assess_density(density)
}
# Overall assessment
total_keyword_occurrences = sum(kw['occurrences'] for kw in keyword_densities.values())
overall_density = (total_keyword_occurrences / total_words * 100) if total_words > 0 else 0
return {
'total_words': total_words,
'keyword_densities': keyword_densities,
'overall_keyword_density': round(overall_density, 2),
'assessment': self._assess_overall_density(overall_density),
'recommendations': self._generate_density_recommendations(keyword_densities)
}
def _build_title_with_keywords(
self,
app_name: str,
keywords: List[str],
max_length: int
) -> Optional[str]:
"""Build title combining app name and keywords within limit."""
separators = [' - ', ': ', ' | ']
for sep in separators:
for kw in keywords:
title = f"{app_name}{sep}{kw}"
if len(title) <= max_length:
return title
return None
def _optimize_short_description(
self,
app_info: Dict[str, Any],
target_keywords: List[str]
) -> Dict[str, Any]:
"""Optimize Google Play short description (80 chars)."""
max_length = self.limits['short_description']
# Focus on unique value proposition with primary keyword
unique_value = app_info.get('unique_value', '')
primary_keyword = target_keywords[0] if target_keywords else ''
# Template: [Primary Keyword] - [Unique Value]
short_desc = f"{primary_keyword.title()} - {unique_value}"[:max_length]
return {
'short_description': short_desc,
'length': len(short_desc),
'remaining_chars': max_length - len(short_desc),
'keywords_included': [primary_keyword] if primary_keyword in short_desc.lower() else [],
'strategy': 'keyword_value_proposition'
}
def _optimize_subtitle(
self,
app_info: Dict[str, Any],
target_keywords: List[str]
) -> Dict[str, Any]:
"""Optimize Apple App Store subtitle (30 chars)."""
max_length = self.limits['subtitle']
# Very concise - primary keyword or key feature
primary_keyword = target_keywords[0] if target_keywords else ''
key_feature = app_info.get('key_features', [''])[0] if app_info.get('key_features') else ''
options = [
primary_keyword[:max_length],
key_feature[:max_length],
f"{primary_keyword} App"[:max_length]
]
return {
'subtitle_options': [opt for opt in options if opt],
'max_length': max_length,
'recommendation': options[0] if options else ''
}
def _optimize_full_description(
self,
app_info: Dict[str, Any],
target_keywords: List[str]
) -> Dict[str, Any]:
"""Optimize full app description (4000 chars for both platforms)."""
max_length = self.limits.get('description', self.limits.get('full_description', 4000))
# Structure: Hook → Features → Benefits → Social Proof → CTA
sections = []
# Hook (with primary keyword)
primary_keyword = target_keywords[0] if target_keywords else ''
unique_value = app_info.get('unique_value', '')
hook = f"{unique_value} {primary_keyword.title()} that helps you achieve more.\n\n"
sections.append(hook)
# Features (with keywords naturally integrated)
features = app_info.get('key_features', [])
if features:
sections.append("KEY FEATURES:\n")
for i, feature in enumerate(features[:5], 1):
# Integrate keywords naturally
feature_text = f"• {feature}"
if i <= len(target_keywords):
keyword = target_keywords[i-1]
if keyword.lower() not in feature.lower():
feature_text = f"• {feature} with {keyword}"
sections.append(f"{feature_text}\n")
sections.append("\n")
# Benefits
target_audience = app_info.get('target_audience', 'users')
sections.append(f"PERFECT FOR:\n{target_audience}\n\n")
# Social proof placeholder
sections.append("WHY USERS LOVE US:\n")
sections.append("Join thousands of satisfied users who have transformed their workflow.\n\n")
# CTA
sections.append("Download now and start experiencing the difference!")
# Combine and validate length
full_description = "".join(sections)
if len(full_description) > max_length:
full_description = full_description[:max_length-3] + "..."
# Calculate keyword density
density = self.calculate_keyword_density(full_description, target_keywords)
return {
'full_description': full_description,
'length': len(full_description),
'remaining_chars': max_length - len(full_description),
'keyword_analysis': density,
'structure': {
'has_hook': True,
'has_features': len(features) > 0,
'has_benefits': True,
'has_cta': True
}
}
def _remove_plural_duplicates(self, keywords: List[str]) -> List[str]:
"""Remove plural forms if singular exists."""
deduplicated = []
singular_set = set()
for keyword in keywords:
if keyword.endswith('s') and len(keyword) > 1:
singular = keyword[:-1]
if singular not in singular_set:
deduplicated.append(singular)
singular_set.add(singular)
else:
if keyword not in singular_set:
deduplicated.append(keyword)
singular_set.add(keyword)
return deduplicated
def _build_keyword_field(self, keywords: List[str], max_length: int) -> str:
"""Build comma-separated keyword field within character limit."""
keyword_field = ""
for keyword in keywords:
test_field = f"{keyword_field},{keyword}" if keyword_field else keyword
if len(test_field) <= max_length:
keyword_field = test_field
else:
break
return keyword_field
def _calculate_coverage(self, keywords: List[str], text: str) -> Dict[str, int]:
"""Calculate how many keywords are covered in text."""
text_lower = text.lower()
coverage = {}
for keyword in keywords:
coverage[keyword] = text_lower.count(keyword.lower())
return coverage
def _assess_density(self, density: float) -> str:
"""Assess individual keyword density."""
if density < 0.5:
return "too_low"
elif density <= 2.5:
return "optimal"
else:
return "too_high"
def _assess_overall_density(self, density: float) -> str:
"""Assess overall keyword density."""
if density < 2:
return "Under-optimized: Consider adding more keyword variations"
elif density <= 5:
return "Optimal: Good keyword integration without stuffing"
elif density <= 8:
return "High: Approaching keyword stuffing - reduce keyword usage"
else:
return "Too High: Keyword stuffing detected - rewrite for natural flow"
def _generate_density_recommendations(
self,
keyword_densities: Dict[str, Dict[str, Any]]
) -> List[str]:
"""Generate recommendations based on keyword density analysis."""
recommendations = []
for keyword, data in keyword_densities.items():
if data['status'] == 'too_low':
recommendations.append(
f"Increase usage of '{keyword}' - currently only {data['occurrences']} times"
)
elif data['status'] == 'too_high':
recommendations.append(
f"Reduce usage of '{keyword}' - appears {data['occurrences']} times (keyword stuffing risk)"
)
if not recommendations:
recommendations.append("Keyword density is well-balanced")
return recommendations
def _recommend_title_option(self, options: List[Dict[str, Any]]) -> str:
"""Recommend best title option based on strategy."""
if not options:
return "No valid options available"
# Prefer brand_plus_primary for established apps
for option in options:
if option['strategy'] == 'brand_plus_primary':
return f"Recommended: '{option['title']}' (Balance of brand and SEO)"
# Fallback to first option
return f"Recommended: '{options[0]['title']}' ({options[0]['strategy']})"
def optimize_app_metadata(
platform: str,
app_info: Dict[str, Any],
target_keywords: List[str]
) -> Dict[str, Any]:
"""
Convenience function to optimize all metadata fields.
Args:
platform: 'apple' or 'google'
app_info: App information dictionary
target_keywords: Target keywords list
Returns:
Complete metadata optimization package
"""
optimizer = MetadataOptimizer(platform)
return {
'platform': platform,
'title': optimizer.optimize_title(
app_info['name'],
target_keywords
),
'description': optimizer.optimize_description(
app_info,
target_keywords,
'full'
),
'keyword_field': optimizer.optimize_keyword_field(
target_keywords
) if platform == 'apple' else None
}