Agentless Monitor is described as 'sophisticated rules engine capable of sensing rule violations within seconds and alerting you immediately. It monitors network, servers, databases, java applications, errors, and exceptions, websites etc'. There are three alternatives to Agentless Monitor for Linux and Android. The best alternative is Nagios, which is both free and Open Source. Other great apps like Agentless Monitor are Trafikito (Freemium) and AppOptics (Paid).