If you are tech-savvy, install a custom ROM like that brings Android 7.1 or higher to older phones (e.g., Samsung Galaxy S4, Moto G). This is complex and voids warranties, but it allows you to install the latest Nequi.
(released 2013). Many modern banking/fintech apps, including Nequi, no longer support KitKat due to security requirements (TLS 1.2+, API level 21+). nequi apk android 44 2