diff --git a/research/smartphone.mdwn b/research/smartphone.mdwn
index 010d246e29bd11670cb507076499609858cf4c9e..a3ad97ac62cdfe76926fd40cbca9f6d1fc6b6437 100644
--- a/research/smartphone.mdwn
+++ b/research/smartphone.mdwn
@@ -212,6 +212,12 @@ Via [Validating the Android 4.2.2 RSA fingerprint](https://shred.zone/cilla/page
 
 ## Instalação manual de apps
 
+Checagem de assinatura:
+
+    apksigner verify --print-certs app.apk
+
+Instalação:
+
     adb install app.apk
 
 ## Movendo arquivos do sdcard para o armazenamento interno