Check out free Security+ exam cram, http://www.examguides.com/security+/index.htm
Free app available with 60 full length questions and answers. Flash card for each question. Check out, https://itunes.apple.com/us/app/ccent-exam-simulator-100-105/id1201594079?mt=8
CCNA Security app with 300+ questions and answers at https://itunes.apple.com/us/app/examsim-ccna-security-210-260/id1203615251?mt=8
Flash card explanation is given for each question.
Check out free CCNA app for iOS/iPhone with 60 questions and answers and flash cards, https://itunes.apple.com/us/app/exam-simulator-ccna-200-125/id1192964788?mt=8
Security+ practice exam app for iOS/iPhone, https://itunes.apple.com/us/app/exam-simulator-for-security/id1204106710?mt=8
Check out C+ Cert exam app for iOS/Apple mobiles at http://www.swregn.com/Products/Exam-Simulator-Aplus-Essential.html
Check out Juniper netsim for JUNOS with dozens of labs, http://www.simulationexams.com/downloads/juniper/jncia-junos-with-network-simulator.htm
PuTTY is a free software that can be download and used. Some commandsm such as ipconfig, nslookup, netstat may be run from DOS prompt for learning.
Packet tracer is also a free software, which requires only registration. However, it's meant for CCNA/CCNP studies and has bit of learning curve.
For network+, there are a few labsims from Certexams.com, Testout, Pearson etc. You may check them out too. Good luck!
But if I want to use Putty I'll need a compatible router or switch right?
If you want to use Putty in real time, you need a server. By using simulator labs, you will be working in virtual environment. Won't be needing any real router or server.
Check out exam sim for Comptia A+ cert, https://itunes.apple.com/us/app/exam-sim-for-a-essentials-220-901/id1204117711?ls=1&mt=8