Knowing when to replace your phone can save you money and frustration. Common indicators include persistent performance issues like lagging apps, a rapidly draining battery, and insufficient storage. Outdated software, lack of security updates, and a cracked screen are also red flags. If your phone no longer supports essential apps, or if the cost of repair outweighs the price of a new device, it's likely time for an upgrade. Consider your budget and desired features when choosing a replacement.