Performance issues can be common, often depending on the location of a remote client accessing a private network. Data loss may occur due to the risk of data transmission over multiple public networks. To combat this, many VPN providers offer quality of service assurance (QoS) to ensure that no data is lost during data transfer.
Also keep in mind that some free Android apps can track users and infect their phones. You should definitely be wary of free Android apps and don’t forget to check user reviews before downloading both free and paid apps.