Use Cold Storage for Long-Term Holdings
If you're holding Bitcoin as a long-term investment, store it in a cold wallet (like Ledger or Trezor) that stays offline. This minimizes exposure to hacks, malware, and phishing attacks.
Cold wallets offer the highest level of protection, especially for significant amounts. While setup may be less convenient than a mobile app, the trade-off in security is worth it.
For long-term investments, it's best to use hardware wallets (such as Ledger or Trezor) or even generate Bitcoin addresses offline. If you don’t plan to use your funds frequently, this option is much safer than any mobile app.
This is the best answer to the question: “Which wallet should I use to store Bitcoin?” — especially when large amounts are involved.